Working the Easy Sats

Working the Easy Sats
WORKING
ORKING THE
THE EASY
ASY SATS
ATS
V v
Where’s my
downlink?
An Informal Introduction to the
Amateur Satellite Program
plus
Hints on Using the More
Easily Accessed Satellites
EL
AT
CQ
CQ
LIT
E
S
by
GARY B. ROGERS, WA4YMZ
AMSAT 16961
Where’s the
beacon?
Forward
This document was created as an attempt to provide a simple easy to read introduction to the
Amateur Satellite Service and easily used “birds” now in operation. Why did I undertake this task?
Simply put, I wanted to share the enjoyment I receive operating the satellites. I’ll tell you up front,
this type of operation isn’t for everybody. Some people will find it too boring, some may see it as
too much effort for the payoff and others may not like the fact that they can’t work the birds
whenever they want. Satellites are but one aspect of the total amateur radio picture. If you think
you may want to give it a try, please do. You may find, as I did, that other operating habits and
pursuits get pushed to the back seat. I also want to dispel the myth that getting on the satellites is
expensive. True, it can suck your wallet dry if you let it, but name any other part of ham radio, or
any other hobby for that matter, that won’t. It need not be that way. I will be concentrating on the
“Easy Sats”, those satellites that do not require lots of extra hardware or big high gain directional
antennas. These satellites can be worked very well with no more equipment than many hams
already own.
I am only able to offer observations, hints, explanations, etc., on those facets of the hobby in
which I am involved. So far, I have limited my efforts to the LEO’s (Low Earth Orbit satellites),
mainly on voice but with some digital work, so I am most able to speak of those. I have no first
hand knowledge of AO-10 or AO-40 other than what I have read or by occasionally monitoring the
downlinks. Besides, these “birds” don’t really fit into the category of “easy” and are beyond the
scope of this paper. I will also be avoiding discussion of the digital satellites now in operation, as
they require more specialized equipment.
This work is very personal. It details what I learned while trying to set up my satellite station. To
that end, I ask that you view it as such. I am basically saying “I did it. You can, too. Come join the
fun!”
Hope to hear you on the birds soon!
Gary B. Rogers
WA4YMZ
AMSAT 16961
WA4YMZ@AMSAT.ORG
Copyright Notice: All rights to this work are the property of the author, but permission to distribute
and copy in whole and without modification is granted to representatives of AMSAT. All others
should contact the author.
Rev. 3.8
April, 2002
2
Contents
Forward ...................................................................................................................................... 2
A brief note on why I wrote this paper and what is included.
Contents ..................................................................................................................................... 3
This listing.
An Introduction to the Satellites .............................................................................................. 4
An overview of what satellites are available to the
Amateur Satellite operator.
Definitions.................................................................................................................................. 9
Some commonly used words in the satellite program.
Special Considerations .......................................................................................................... 12
A look at some of the major differences between
terrestrial operation and using the satellites.
The Easy Sats .......................................................................................................................... 16
A definition of what we consider Easy Sats and a
look at those that meet our definition. Discussed are:
RS-12/13
UO-14
RS-15
FO-20 and FO-29
AO-27
ARISS
Working the Birds ................................................................................................................... 21
A suggested path for getting active on the
Easy Sats, with hints for setting up your station.
More Boxes, More Satellites .................................................................................................. 24
A brief peek at what lies ahead for the satellite
operator who decides to go beyond the Easy Sats.
After the QSO .......................................................................................................................... 27
Information on QSLing, Grid Squares and Certificates.
How One Ham Got On the Satellites ..................................................................................... 30
A discussion of what it took for me to become satellite
active, with a look at some of my successes and problems.
My Resources .......................................................................................................................... 33
A bibliography of the books, e-mail lists and on-line
resources I used while researching this paper.
AMSAT ...................................................................................................................................... 35
The Radio Amateur Satellite Corporation, our international
organization of Amateur Satellite operators.
In Closing... .............................................................................................................................. 36
A few final thoughts.
3
An Introduction to the Satellites
Are you ready to get started? Great! Since this is the Amateur Satellite program, let’s have a look
at the Amateur Satellites. The first thing we’ll notice is that there are quite a few of them and no two
are exactly the same. Fortunately, there are enough similarities among some of the birds that we
can conveniently group them. For lack of any better reason than this is how I think of them, I have
divided all of the active satellites into the following four categories. Some of the satellites appear
more than once because they operate in more than one manner.
1) Low Earth Orbit - Analog (CW and Voice)
RS-12/13, UO-14, RS-15, FO-20, AO-27, FO-29
2) Low Earth Orbit - Digital
AO-16, FO-29 (1200 Baud)
UO-22, KO-23, KO-25, TO31, UO-36
3) High Earth Orbit
AO-10, AO-40
4) Occupied Spacecraft
ARISS (International Space Station)
At this time, nearly three quarters of the Amateur Satellites fall into the group we call “LEO - Low
Earth Orbit”. If we include the Occupied Spacecraft, which share the same orbital characteristics,
we’re left with only AO-10 and AO-40. One common feature of these birds is that they circle the
earth many times a day and are usually available two or three times during one part of the day and
as many times about 12 hours later. Due to their low orbit and the sensitive receivers they all
possess, directional antennas and lots of power are not required. Many hams already own the
equipment needed to work the satellites, they just don’t realize it. That’s one of the reasons I have
written this paper.
Unfortunately, a disadvantage to a low orbit is that the satellites’ footprints (area “seen” by the
satellite at any one time) are small and their passes are short. Consequently, people who use
these birds generally limit themselves to very short QSO’s or even use the quick contact format
similar to that used during contests. Do not let this dissuade you from trying them, however. They
really are easy to use, and some of them, the Russian birds we call the RS series (for Radio
Sputnik), are also relatively inexpensive to get on.
Since this is an introduction to the satellites, I’ll be concentrating on what we call the Easy Sats.
What defines an Easy Sat? Well, how about:
1) Easy to hear?
2) Easy to aim your antennas? (Not necessary if you’re using omni’s!)
3) Easy on the check book?
There are presently six analog satellites (RS-12, UO-14, RS-15, FO-20, AO-27, FO-29) and the
Occupied Spacecraft that meet these requirements. It is on these that we will concentrate. By the
way, by “Easy on the check book” I mean that nothing is required to work these birds that can’t be
used for standard terrestrial Hamming: An HF radio and a 2m radio (preferably a multimode).
Optional are a packet station for digital work and receive preamps. To be honest, maybe we should
call UO-14, FO-20, AO-27 and FO-29 “Almost Easy Sats” because they require a receiver, transceiver or receive converter for 70cm.
Now let’s take a quick look at the satellites that are presently active in the Amateur Satellite
Service. This chart is an expanded updated version of an old edition of the ARRL Server document
SATFREQS.TXT. I have divided the satellites into the four categories I used above.
4
AMATEUR RADIO SATELLITE FREQUENCIES
Low Earth Orbit - Analog
Designation
Frequencies
(in MHz)
Transp/
Beacon
RS-12 (RS-12/13, NORAD 21089) (2)
Downlinks
29.408
29.410 - 29.450
29.454
145.910 - 145.950
Uplinks
21.210 - 21.250
145.910 - 145.950
Mode
(1)
B
T
B
T
T
T
Notes
Additional notes follow list
T
K
A
CW
CW/SSB
CW (Robot)
CW/SSB
CW/SSB
CW/SSB
J
J
FM Voice
FM Voice
A
T
CW
CW/SSB
CW/SSB
FO-20 (Fuji-OSCAR 20, NORAD 20480) (2)
Downlinks
435.795
B
435.800 - 435.900
T
Uplink
145.900 - 146.000
T
J
J
CW
CW/SSB
CW/SSB
AO-27 (OSCAR 27, AMRAD, NORAD 22825) (3)
Downlink
436.795
Uplink
145.850
J
J
FM Voice
FM Voice
K
UO-14 (OSCAR-14 NORAD 20437)
Downlink
435.070
Uplink
145.975
RS-15 (RS-15, NORAD 23439)
Downlinks
29.352
29.354 - 29.394
Uplink
145.858 - 145.898
B
T
T
FO-29 (Fuji-OSCAR 29, NORAD 24278) (also see 1200 and 9600 Baud)
Downlinks
435.795
B
CW
435.800 - 435.900
T
J
CW/SSB
Uplink
145.900 - 146.000
T
J
CW/SSB
Downlinks
435.910
B
FM Voice digitalker
435.795
B
12WPM CW telemetry
SO-41 (SAUDISAT-1A, NORAD 26545)
Downlink
436.775
Uplink
145.850
J
J
FM Voice
FM Voice
Low Earth Orbit - Digital (1200 Baud) (4)
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
AO-16 (OSCAR 16, Pacsat, Microsat-A, NORAD 20439)
Downlinks
437.025
T/B
J
437.051
T
J
2401.14280
B
Uplinks
145.900
T
J
145.920
T
J
145.940
T
J
145.960
T
J
5
Notes
Additional notes follow list
1200 bps PSK SSB
1200 bps PSK SSB
1200 bps PSK SSB (Usually off)
1200 bps AFSK FM
1200 bps AFSK FM
1200 bps AFSK FM
1200 bps AFSK FM
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
Notes
Additional notes follow list
FO-29 (Fuji-OSCAR 29, NORAD 24278) (also see Analog and 9600 baud)
Downlink
435.910
T
J
1200 bps PSK SSB
Uplink
145.870
T
J
1200 bps AFSK FM
NO-44 (PC-SAT NORAD 26931)
Downlink
145.827
Uplink
145.827
APRS
APRS
Low Earth Orbit - Digital (9600 Baud) (5)
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
Notes
Additional notes follow list
UO-22 (OSCAR 22, UoSAT, UoSAT-F, NORAD 21575)
Downlink
435.120
T
J
Uplinks
145.900
T
J
145.975
T
J
9600 bps FM
9600 bps FM
9600 bps FM
KO-23 (OSCAR 23, KITSAT-A, NORAD 22077)
Downlink
435.175
T
Uplinks
145.900
T
145.850
T
J
J
J
9600 bps FM
9600 bps FM
9600 bps FM
KO-25 (KITSAT-B, NORAD 22828)
Downlink
436.500
Uplink
145.980
J
J
9600 bps FM
9600 bps FM
T
T
FO-29 (Fuji-OSCAR 29, NORAD 24278) (see also Analog and 1200 Baud)
Downlink
435.910
T
J
9600 bps FM
Uplink
145.870
T
J
9600 bps FM
TO-31 (TMSAT-1, NORAD 25396)
Downlinks
436.925
436.900
436.950
436.975
Uplinks
145.925
145.975
T
T
T
T
T
T
J
J
J
J
J
J
9600 bps FM
9600 bps FM
9600 bps FM
9600 bps FM
9600 bps FM
9600 bps FM
UO-36 (Uosat-12, NORAD 25693) (7)
Downlink
437.025
437.400
Uplink
145.960
145.500
T
T
T
T
J
J
J
J
9600, 38400 bps FM
9600, 38400 bps FM
9600 bps FM
9600 bps FM
High Earth Orbit
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
AO-10 (OSCAR 10, Phase 3B, NORAD 14129)
Downlinks
145.810
B
145.825 - 145.975
T
Uplink
435.030 - 435.180
T
B
B
6
Notes
Additional notes follow list
CW
CW/SSB
CW/SSB
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
AO-40 (OSCAR 40, Phase 3D, NORAD 26609)(8)
Downlinks 2401.650 - 2401.950 T
2401.225 - 2401.475 T
24048.450 - 24048.750 T
24048.025 - 24048.275 T
Uplink
435.300 - 435.550
T
435.550 - 435.800
T
1269.000 - 1269.250 T
1269.250 - 1269.500 T
1268.075 - 1268.325 T
1268.325 - 1268.575 T
2401.323
B
24048.035
B
S2
S2
K
K
U
U
L1
L1
L2
L2
S2
K
Notes
Additional notes follow list
DIGITAL
CW/SSB
DIGITAL
CW/SSB
DIGITAL
CW/SSB
DIGITAL
CW/SSB
DIGITAL
CW/SSB
Middle
Middle
Occupied Spacecraft
Designation
Frequencies
(in MHz)
Transp/
Beacon
Mode
(1)
ARISS (International Space Station) (NORAD 25544) (6)
Downlink
145.800
Uplink
144.490
Uplink
145.200
Uplink
145.490
Notes
Additional notes follow list
Worldwide voice/packet
Region 2 & 3 voice
Region 1 voice
Worldwide packet
Notes:
(1) Mode refers to the uplink/downlink band pair used, and is designated with a letter. Modes
presently used are:
A
145 MHz up / 29 MHz down
B
435 MHz up / 145 MHz down
JA 145 MHz up / 435 MHz down - Analog modulation
JD 145 MHz up / 435 MHz down - Digital modulation
K
21 MHz up / 29 MHz down
S
435 MHz up / 2.4 GHz down
T
21 MHz up / 145 MHz down
Some satellites operate in more than one mode at a time, i.e. RS-13 in mode KT.
AO-40 will use the newer mode designations listed in the frequency chart. For instance, J will
become V/U. For more new designators, see the listing on AO-40.
(2)
RS-12/13 is a piggyback package attached to COSMOS 2123
FO-20 is a piggyback package attached to JAS 1-B
(3)
AO-27 is a dual purpose satellite, and is only available for Amateur Radio use at specific times.
The parent satellite is EYESAT-1.
(4)
All 1200 baud satellites except FO-29 require the use of PACSAT protocol software such as PB/
PG for DOS or WiSP for Windows. All 1200 baud satellites require a PSK modem and SSB
receiver.
7
(5)
All 9600 baud satellites except FO-29 require the use of PACSAT protocol software such as
PB/PG for DOS or WiSP for Windows. FO-29 may be accessed using standard packet software.
(6)
The 1200 baud digital system on ARISS may be accessed using standard packet software.
(7)
Includes provisions for downlinking pictures of Earth.
(8)
AO-40 has yet to be fully tested. This frequency list is based on transmitters and receivers
functioning as of April 2002.
The NORAD number listed by each satellite is a designation assigned by the North American Air
Defense Command, a cooperative international group that includes among its duties the tracking
of all space borne objects. This number is used by all popular tracking and pass prediction software to identify which satellites to process.
8
Definitions
Before we go any further, we need to establish a common vocabulary. Some people would put
this in the back, as an appendix or something, but let’s face it, there are a lot of words and terms
that we’ll be using, some of them unique to the satellites.
ANALOG: A type of transmission where the intelligence (voice, CW, SSTV, etc.) is used to directly
control the output of the transmitter. The opposite of DIGITAL.
AOS: Acquisition of Signal. This is the moment when the satellite comes into range and can be
accessed. The easiest way to know you have achieved AOS it to listen for the beacons on the
satellites that have them. The opposite of LOS.
APOGEE: The point in a satellite’s orbit where it is farthest from the earth.
AZ/EL: Azimuth/Elevation. Used to describe the present location in space of a satellite. The Azimuth is the compass direction from the viewer and the elevation is the angle above ground. Also
used to describe the type of hardware able to position antennas in both the horizontal and
vertical planes.
BEACON: An automatic transmitter at the satellite. The beacon is usually located at the high or
low end of the passband and will send out satellite identification and telemetry. Most beacons
use CW.
BIRD: A common slang term for a satellite.
DIGITAL: A method of transmission where the intelligence is processed by some type of modem (a
TNC, for example). Digital satellite communications are usually confined to the LEO packet
satellites. The opposite of ANALOG.
DOPPLER SHIFT: The change in frequency of a received signal due to the motion of the satellite.
This requires adjustment of the transmit or receive frequency, with the common practice being to
change the higher of the two frequencies in use.
DOWNLINK: The transmission from the satellite to the earth station.
EARTH STATION: The equipment used to communicate with or through a satellite or spacecraft.
Special earth stations, known as Control Stations or Command Stations, are able to manipulate
the workings of the satellite.
FOOTPRINT: The area of the earth’s surface which is visible to the satellite at one time. Generally
speaking, the lower the orbit, the smaller the footprint.
FULL DUPLEX: The ability to transmit and receive at the same time. This is the preferred method
in satellite operations because it allows us to hear our own signal and make frequency adjustments as necessary. (See DOPPLER SHIFT)
HALF DUPLEX: Using different frequencies to transmit and receive, but being able to do only one
of those functions at a time. An example of half duplex operation is the use of a single HF
transceiver for Mode K. Not to be confused with SIMPLEX.
INCLINATION: The angle of an orbit in relationship to the equator. Orbits with a low inclination are
called equatorial orbits; those with higher inclinations are called polar orbits.
KEPLERIAN ELEMENTS (KEPS): A set of numerical data that describes a satellite’s orbital characteristics. The use of this information allows tracking programs to determine where that satellite
9
is at any one time, to predict passes and plot ground tracks. Keplerian elements should be
updated every few weeks for stable orbits and more frequently if the object’s orbit is accidentally
(re-entry or collision with another object) or purposely altered (orbital corrections or space craft
maneuvers).
LEO: Low Earth Orbit. A name given to satellites with orbits in the 600 to 2000 kilometer altitude
range. The LEOs normally circle the earth about every 1.5 to 2 hours. Their low altitude gives
rise to a small footprint and their speed causes the pass to be of short duration.
LOS: Loss of Signal. The moment when the satellite can no longer be heard.
MODE: An indication of the operational parameters of a satellite, including frequencies used and
types of modulation. These are noted with a series of letters.
A:
145 MHz up / 29 MHz down. SSB and CW.
B:
435 MHz up / 145 MHz down. SSB and CW.
JA: 145 MHz up / 435 MHz down. SSB and CW. The A means Analog.
JD: 145 MHz up / 435 MHz down. FM Packet uplink. PSK downlink on 1200 baud satellites,
FM Packet on 9600 baud satellites. The D means Digital.
K:
21 MHz up / 29 MHz down. SSB and CW. In the US this mode is limited to Advanced and
Extra Class licensees.
S:
435 MHz up / 2.4 GHz down. SSB and CW. Many people use receive converters for the
downlink.
T:
21 MHz up / 145 MHz down. SSB and CW. Not much available for this any more, but
sometimes RS-12 will be in this mode, or mode KT, with a 21 MHz uplink and downlinks
on both 29 MHz and 145 MHz.
With the launch of AO-40, this type of designation will become obsolete. AO-40 will employ a
matrix of receivers and transmitters which will be engaged at various times, so the shorter one or
two letter combinations will be replaced with an indication of which TX and RX pair is active. For
example, Mode J will become Mode V/U, for VHF up/UHF down.
MOLNIYA: A type of elongated orbit where, as the satellite nears its apogee, it seems to be almost
motionless for long periods of time. Very good for long distance contacts.
OSCAR: Orbiting Satellite Carrying Amateur Radio. The original name for the satellite program.
Project OSCAR was later replaced by AMSAT but the name still remains in the designations.
PASSBAND: When used in reference to a TRANSPONDER, defines the amount of radio spectrum that a receiver will accept and, consequently, the amount of radio spectrum a satellite’s
downlink will occupy.
PERIGEE: The point in a satellite’s orbit where it is closest to the earth.
REPEATER: A radio system that receives a radio signal on one frequency and retransmits it on
another, usually on a different band. Repeaters work with one signal at a time and should not be
confused with a TRANSPONDER.
STORE & FORWARD: Technique used with the digital satellites in which a message or file is
transmitted up to a satellite where it is stored. This information is then retransmitted and received by another station who requests it. Very similar to having a friend upload a file to your
favorite telephone or packet BBS and letting it sit until you are able to log on and retrieve it.
10
TRACKING: The process of continuously adjusting the direction of antennas to keep them aimed
at a moving satellite. Also the use of a computer program to generate and/or display the position
of the satellite. Some of the more advanced satellite operators have the computer linked to the
antenna aiming control boxes so this function is done without human intervention.
TRANSPONDER: Similar to a repeater, but a range of frequencies is converted from one band to
another. This range of frequencies is known as the PASSBAND of the transponder. There are
two types of transponders: Non-Inverting and Inverting. A Non-Inverting transponder will receive
an USB (Upper Side Band) signal at the high end of the Uplink Passband and it will appear as an
USB signal at the high end of the Downlink Passband. Examples of a Non-Inverting transponder
are RS12 and RS-15. With an Inverting Transponder, to receive that same high end USB signal,
you would transmit a LSB (Lower Side Band) signal at the lower end of the Uplink Passband.
Examples of Inverting transponders are AO-10, FO-20 and FO-29.
UPLINK: The signals from the ground station to the satellite.
11
Special Considerations
I can hear you thinking “Whoa! I thought you said these were easy to work! That whole list of
satellite specific words sure doesn’t look easy to me!” There really isn’t a problem here. All of these
will come as second nature once you get on the birds. Like many things in life, it’s hard to understand something if you don’t know the terms. There are a few concepts we really should spend
more time discussing, though, because they are unique to satellite operation. If we aren’t at least
familiar with them, getting started will be much more difficult
The biggest difference between satellite communication and the type of Hamming we are all
used to is that you can’t just pick up the microphone, start talking, and expect someone to be there
listening. Working a satellite is more like working DX or holding a schedule with another Ham. For
example, maybe you want to talk to your friend in another state. On HF you would ask yourself
“What band can I use to get there and when will it be open?” You ask much the same thing on the
satellites only it would be “What satellite can I use with my equipment and when will it be in a
location where it is visible to us both?” Well, let’s assume you have a station set up for Mode A. You
know that Mode A is available on RS-12 and RS-15, so you fire up your computer, load your
favorite pass prediction program, and see that you have a common window of visibility at 1330
UTC on RS-12. At the appointed hour you fire up the radios and start talking to your friend.
Well, not really, and what’s all this about computers and what are pass prediction programs? By
their very nature, the LEO’s are constantly moving. This can create quite a problem unless you
have a way to determine where they will be at any given minute. There is a lot of math involved and
you need to know such things as altitude, speed, direction, drag coefficient and a bunch of other
goodies that describe exactly a satellite’s orbit. This information is generated by USSPACECOM
and distributed through a variety of networks and can be downloaded from many bulletin boards.
Fortunately, the orbital parameters of a satellite varies little on a day by day basis, so updating
these Keplerian Elements (that’s what they are called) only needs to be done every few weeks. In
the days B.P.C. (Before Personal Computers), people had to manipulate this information by hand
or with a calculator. Now programs exist that will take these elements, do all of the computations
for you, and generate a list of pass opportunities. Most of the better ones will even show you this
graphically. The quality of these programs varies, as do their hardware requirements and cost.
Prices can range from free up to $90 or so and, depending on what you need, your computer could
range from a very simple to a super fast system. You will need an accurate clock for real-time
tracking, and you should know your geographical coordinates (latitude and longitude). Don’t worry
too much about the latter; the better programs have a list of sites built in and you just need to pick
your nearest major city. You will often hear this pass prediction called “tracking.”
So now we know what satellite and when it will be coming over. We’re ready, right? Well, we
would be if it were exactly that easy. Going back to our example, let’s compare the satellite with the
band and the pass time with when the band is open. If either of those isn’t present, you’re out of
luck, but if both are available, you still have to know the exact frequency. If you want to talk with
someone specific, you had better agree on that ahead of time. Fortunately, most of us just want to
communicate, or perhaps we’re trying to achieve Worked All States on the satellites. Then it’s just
like we’re used to operating; call CQ or answer someone else’s.
Transponders and Satellite Passbands
Another comparison between satellite and non-satellite operation is that working satellites is
very similar to working “split” on HF or “cross-band” repeat on repeaters, where you transmit on
one band and listen on another. On HF, you are pretty much free to choose which two bands and
which frequencies within those bands you wish to use. On the satellites, as on the repeaters, that
choice has been made for you; that’s what we mean by “mode”. Unlike repeaters, almost all of the
12
analog birds are actually “transponders” which listen to an entire segment of one band and retransmit it on another band (the exceptions are UO-14 and AO-27). Let us again go back to your
planned QSO with your out-of-state friend. You chose RS-12, a Mode A satellite. RS-12 will accept
a signal anywhere from 145.910 MHz to 145.950 MHz and retransmit it between 29.410 MHz and
29.450 MHz. These are known as the uplink and downlink passbands, and there is a direct relationship between them. A signal you transmit a 145.920 MHz will be rebroadcast by the satellite at
(about) 29.420 MHz, 145.930 MHz comes down as (about) 29.430 MHz, etc. This is because RS12 (as well as RS-15) uses what is known as a “non-inverting linear transponder”.
You can easily graph this relationship, and it may not be a bad idea to do so. Using a ruler, draw
two parallel lines of equal length, one exactly above the other. Look up the passband limits of the
satellite in question. Note the lower limit of the uplink at the left end of the top line and the upper
limit on the right end. Do the same for the downlink on the bottom line. What you end up should
look something like this (all frequencies are in MHz):
RS-12 Uplink Passband
145.910
145.920
145.930
145.940
145.950
+ ——————— + ——————— + —————— + ——————— +
+ ——————— + ——————— + —————— + ——————— +
29.410
29.420
29.430
29.440
29.450
RS-12 Downlink Passband
Looking at this, you can see that if you want to meet your friend on a downlink frequency of
29.440 MHz, you just need to transmit on (about) 145.940 MHz.
Doppler Shift
Wait a minute! What’s with this “about” stuff? Unlike terrestrial communications where it is possible to pick a frequency and stay there (+/- drift for older radios), there is a phenomenon known as
Doppler Shift that satellite operators must take into account. Just what is this Doppler Shift and
how do we deal with it? By way of another example, have you ever heard a train blowing its whistle
as it passed by? Remember how the tone seemed to change with time? Obviously, the whistle
wasn’t actually changing; it was how you perceived the whistle that changed. This variance is a
result of the relationship of the observer to a source that’s moving. Well, that is what we call
Doppler Shift. The same thing happens to signals coming from space, but because the signals we
receive are transmitted as RF instead of audio and the signal source is traveling at about 17,000
miles per hour and not at 60 to 70 miles per hour like our train, we have to constantly tune our
receivers or transmitters to make up the difference. On the Amateur satellites we’ve developed a
de facto standard of changing the higher of the two frequencies. For example, if I’m listening to
myself on the RS-12 downlink, I’ll constantly fine tune my uplink because it is the higher of the two
(145 MHz vs 29 MHz). Technically speaking, the satellite also sees a shift in the signal it is receiving, so I’m compensating for both. The apparent shift in frequency varies by band. On RS-12 with
its 2m uplink and 10m downlink, the change is on the order of +/- 2.5 kHz. Up on FO-20 and FO29, where the uplink is 2m and the downlink is 70cm, the shift grows to +/- 10 kHz.
The hardest part about Doppler Shift is finding your desired signal the first time, but even that
isn’t a major hassle. Let’s go back to our RS-12 example. This time, let’s say that you have a
schedule with your friend and you have both agreed to meet on the downlink frequency of 29.440
MHz. You know that for that frequency down, you need to transmit on about 145.940 MHz. You
also know that Doppler is going to be changing that somewhat, but how much you need to deter13
mine. What do you do? Listen for the RS-12 beacon, that’s what. You consult the satellite information table and see that the beacon is supposed to appear at 29.408 MHz. Tuning there, you find the
beacon, loud and strong, at 29.410 MHz instead. Ah, hah! The beacon is 2 kHz HIGHER than it
should be. Now we’re ready. Quickly, tune your receiver back down to 29.440. Next, correct your
transmitter frequency by tuning it LOWER by 2 kHz to 145.938 MHz. Give a few quick dits on your
key or announce your call and you should hear yourself. You may not be exactly on frequency, but
you’re pretty close. After that, just make minor corrections to your transmitter or receiver as necessary. (To accomplish this, it really helps to be able to listen to your downlink. That’s one of the
advantages of full duplex operation.) By the end of the pass, you’ll notice that you are actually
above your original non-corrected target frequency, but you’ve done it: you made another successful contact!
Sure seemed like a lot of trouble, didn’t it? Don’t worry; in time it will be second nature. You won’t
even have to hunt for the beacon, you’ll just know where to start listening for your signal.
That sounds fine for the SSB/CW satellites, but what about those FM uplinks? Don’t the satellites see a variance in those, too? Yes, they do, but their receivers were purposely built a bit broad
so it isn’t a problem. We worry ONLY about the downlink.
Antennas
Before we leave this topic, let’s spend just a little time on the “best antenna” debate. Unless you
have the time, space and inclination to put up directional antennas for the satellites, you must
decide just how much of a compromise you are willing to make. If you run one of the pass prediction programs that lists the maximum angle the birds achieve when you can access them, you will
see that most of the time they are no higher than 35 degrees or so above the horizon. Unfortunately, the closer to the horizon a satellite, the greater the distance from the observer, the higher
the path loss and the greater the transmit and receive gain needed to successfully work the bird.
Verticals cover this well, especially ones with some gain. Be very careful with your choice if you
go this way, though; some of the really high gain verticals are optimized for low angles of radiation
and the signal strength falls off rapidly as your elevation angle increases. Another problem with
verticals is that natural and man-made noise tends to be vertically polarized. With FM signals this
isn’t a problem, but with SSB and CW it is very apparent.
Dipoles also work well, especially for the Mode K uplink and Mode K and A downlinks, but they
have a tendency to suffer from loss of gain off the ends. For good coverage using dipoles, it isn’t a
bad idea to have two at right angles from each other. The turnstile is a special nifty antenna
composed of two dipoles fed in parallel by a 1/4 wavelength section of feedline at about 92 ohms.
This will yield a total impedance of around 50 ohms making your receiver or transmitter happy. The
horizontal radiation pattern is omnidirectional but its vertical angle of radiation varies by its height
above ground. Like the dipole, you need to pay attention to this height. At about 3/8 wavelength
above ground the pattern looks somewhat like a round balloon that has been put on a flat surface
and is being slightly depressed in the top center. This gives more gain toward the horizon and less
directly overhead where the closeness of the satellite makes it less necessary. The TR-Array is a
favorite home brew application of the turnstile where the crossed dipoles are mounted above an
artificial ground, such as a section of chicken wire in a frame. These are often used at 2m and
above. Because the ground plane is part of the antenna system, it can be mounted well above the
actual ground.
If you are fortunate enough to have beams, an old trick is to tilt them about 30 degrees up.
This will still give you gain toward the horizon but increases the usable elevation. Don’t feel you
must tilt your antennas, though, especially if you are using a mono-bander or tri-bander for RS-12
or for the downlinks of RS-12 or RS-15. Many satellite operators report excellent results in the
14
standard “flat” horizontal orientation. The only disadvantage to using beam antennas is you will
need to continuously correct their direction as the satellite moves by. On the LEO’s, with their fast
relative velocities, this may be a challenge for the new operator.
If you enjoy building at least part of your station, consider making your own antennas. At the
frequencies used by the Amateur satellites, the sizes aren’t bad and it is possible to obtain a lot of
gain in a small (relative to HF) size. Antennas need not be expensive, so this is a good way to try
out those “what if...?” and “I wonder...” theories without sacrificing your life savings.
No matter which antenna you decide to use, don’t forget the importance of using a high quality,
low loss transmission line and good connectors. Use the very best you can afford because, if you
skimp here, you could loose a significant part of your signal as line loss. If it were only on transmit
that this happened, you could make up for it with increased power (wasteful), but losses occur on
receive, too. Every dB of attenuation from the antenna to the radio is a bit of the downlink you can’t
hear and the 3-6 dB loss possible from using the wrong coax can turn a marginal signal into one
that simply isn’t there. The connectors you use add to this loss in a subtle way by creating an
impedance “hump” that acts like a little resistor in the line. At HF, and to some extent at 6m and 2m,
we can get by with using the common SO-239/PL-259 combination, but at higher frequencies,
such as 70cm and up, most equipment comes equipped with the Type-N connector. The Type-N,
properly installed, will cause a very small mismatch, allowing all of the signal to makes its way to
and from the antenna. One final point to be observed is to make sure that the connector/coax is
well seated and well sealed when installed on the antenna. If you don’t keep the weather out of the
connection, your coax will become waterlogged and then you’ll really have line losses. One popular method is to wrap electrical tape tightly around the connectors, then use one of the many
available hand-moldable compounds sold just for this purpose.
A Friendly Warning:
Once you have everything set up and start to make contacts on the birds, you may find that you’ll
be running that pass prediction program quite often so you can see when the next opportunity to
talk ANYWHERE on ANY satellite comes up. It’s kind of like getting bit by the radio bug all over
again.
15
The Easy Sats
Okay, now we’re ready to look at the Easy Sats. The next several pages will be a more in depth
discussion of each satellite, including notes, observations and, in some cases, a bit of that bird’s
history. For lack of a better reason than it makes sense to me, I chose to review them in ascending
order. Interestingly enough, the difficulty level rises with each, but only slightly. ARISS is presented
last only because it has no numeric designator. Following this section, I’ll discuss an easy upgrade
path for your satellite career.
RS-12/13
RS-12/13 is in a 990 km high polar orbit giving it a coverage circle (footprint) of about 6400 km,
sufficient to reach significant portions of the United States at one time when the satellite is over the
middle of the country. Passes over the eastern US give access to Europe, and Hawaii can be
reached if the bird is over the west coast. The low orbit carries it over the US six to eight times a
day for 10-18 minutes at a time, with three passes spaced a little over 1.5 hours apart, and three
more about 12 hours later.
RS-12/13 is actually a “piggyback”, box that is bolted to a larger Russian satellite. It draws its
power from the parent satellites’ systems, allowing it to have a higher power budget than most of
the other LEO’s. Because of this, many fledgling Amateur Satellite operators have their first satellite experience by monitoring their 10m downlinks using simple dipole antennas. In actuality, RS13 is a backup to RS-12 and it shares the frame with its primary counterpart. For convenience, we
will refer to this satellite just as RS-12.
RS-12 is equipped with a 40 kHz wide analog (SSB and CW only) transponder, divided into ten
4 kHz wide AGC controlled segments. Because of its very sensitive receivers, the builders used
this “segmentation” technique to prevent one or two very strong signals from using up the entire
downlink power budget. This works fairly well, but excessively strong uplinks can and will still be
heard several kHz away. If you feel the need to increase your output power so you have a louder
signal, consider working on your receiver setup instead. No one likes an “alligator”, and you may
find that you are just talking to yourself because no one else wants to encourage poor operating
practice. Remember: 100 watts effective output is all you need, and many enjoyable contacts are
possible using much less.
A unique function of this satellites is an automated CW ROBOT, transmitting on the beacon
frequencies. If you hear the ROBOT calling CQ, it will give the proper uplink frequency. Transmit
the following at around 20 WPM (anything from about 12 WPM will work):
RS-12 DE (your call) AR
and the ROBOT will respond with
(your call) DE RS-12 QSL NR (number) OP ROBOT TU USW QSO (number) 73 SK
To receive a QSL card for your ROBOT contact, you must send the QSL number the ROBOT
sent back to you on your QSL card. At the present time, there is no assigned QSL manager for
ROBOT contacts. However check the following web page for the latest information.
http://www.amsatnet.com
Select “RS Robot QSL Route” near the bottom of the page. If you do QSL, please remember to
send along an SASE with sufficient postage.
16
You may read from time to time about people who use their FM handi-talkies to operate CW on
RS-12. Although this is possible, it is not encouraged. FM signals are very wide band and even
though there is no effort to transmit audio, unless the microphone is totally disconnected, you will
put an FM signal into the bird. Some newer 2m FM radios also have a problem with a slow lockup
time for their synthesizers and the resultant signal is “chirpy”.
RS-15
RS-15 is another of the Russian Sputnik series of Ham Satellites. Despite a common heritage,
there are several differences between it and RS-12. For the Mode A operator, newcomers especially, this can be a mixed blessing. Although a LEO like its brothers, RS-15’s orbit is much higher
and passes lasting up to 30 minutes are not uncommon. It’s nice to be able to hold a conversation
with someone and not have to worry about hitting LOS in mid-sentence. Another advantage of the
higher orbit is that it provides a much larger footprint. When over Raleigh, NC the entire continental United States can be worked. When RS-15 is over the mid-Atlantic, it is possible to easily reach
Europe.
Unlike RS-12, RS-15 is an independent satellite, not attached to a larger space frame. For a bird
that weighs in at only 70 kg and is only about one meter in diameter, that means the craft has a
very small power budget. Also, unlike the other RS satellite, please do not attempt to have your
downlink on a par with the beacon; the power allocated to each of the 4 kHz subpassband channels is only about 0.4 W, and the beacon is running about 1.2 W. Many users of RS-15 find that a
receive preamp can be of great benefit, often making the difference in hearing the satellite and
making a contact, or just barely being able to tell that it is there.
Unfortunately, it was noticed soon after launch that the power output drop during times of heavy
use, although anticipated, was much greater than had been expected. Investigation has revealed
that the battery system just isn’t holding up as wished. The satellite’s orbit is also a factor in that the
amount of time that it spends in eclipse (no sun reaching it to recharge the batteries) varies over a
matter of weeks from about 12 minutes per orbit to over 30 minutes per orbit. When you add
lowered recharge time to heavy usage, the power system just can’t keep up and the signal drops
out. In fact, the battery system has now degraded to the point that when the satellite is in total
darkness, the transponder shuts down. As long as these limitations are taken into consideration,
operation through RS-15 can be rewarding.
Another trait of this bird is the very apparent fluctuation of the downlink signal. RS-15 is not spinstabilized, so the satellite is slowly tumbling in its orbit and the relationship of the ground stations
to the satellite’s antennas change. This imparts the flutter or “whooshing” that is characteristic of
the signal.
FO-20 and FO-29
Fuji-2/OSCAR-20, or simply FO-20, is the second in a series of Japanese Amateur satellites.
The orbit of FO-20 is slightly elliptical, so the satellite receives a large amount of illumination
throughout most of the year. It also has an orbit altitude of 1320 km giving it a decent footprint.
When launched, FO-20 was operational in both the digital and analog modes, but now seems to
be permanently set to analog. Just like the larger AO-10, the transponder on FO-20 is inverting, so
whatever goes up on the low end of the uplink passband comes out on the high end of the downlink passband, LSB up becomes USB down, etc. Operating FO-20 is not any different from any
other bird; just use about 100w EIRP and remember to tune the downlink for Doppler. Keep in
mind the inverting transponder and you’re all set. Not only will you transmit on LSB and receive on
USB, but the frequencies track in opposite directions.
17
If you graph this type of transponder, the uplink passband’s lower limit is over the downlink
passband’s higher end, and visa versa, like this (all frequencies are in MHz):
FO-20/FO-29 Uplink Passband
145.900
145.925
145.950
145.975
146.000
+ ——————— + ——————— + —————— + ——————— +
+ ——————— + ——————— + —————— + ——————— +
435.900
435.875
435.850
435.825
435.800
FO-20/FO-29 Downlink Passband
FO-29, launched in the fall of 1996, is virtually identical to FO-20 in regard to use of its analog
transponder, even sharing the same passbands, so operation on this bird is no different than on its
older sibling. Unlike FO-20, FO-29 is also active in the digital mode, with a packet BBS operating.
Only one mode is available at one time, operating on a “round-robin” schedule, so don’t expect the
linear translator to be available at all times.
Until you get used to it, you’ll probably have the tendency to tune in the wrong direction. Also,
bear in mind that by convention you should tune the receive frequency since it is the higher of the
two being used, although some people do it the other way around and it will be necessary to
operate “backwards”. A proposal has been made and is being implemented in the top 20kHz of the
downlink passband where computer control of the radio’s transmit and receive sections are both
tuned to maintain a frequency “at the satellite”. This is made possible because many tracking
programs are able to calculate the required Doppler shift offset and provide it through Terminate
and Stay Resident programs (TSRs) to other programs which provide frequency data to the radio
via a serial, parallel, or dedicated communications port. Of course this assumes that the radio in
use is capable of computer control, but some older models and practically all newer models are so
equipped The operator simply sets the desired frequency and lets the computer do the rest,
getting rid of the necessity of tweaking for Doppler shift and allowing full concentration on the QSO
itself, making this the perfect method for satellite carried nets and scheduled contacts. Right now,
FO-20 and FO-29 are underutilized and non-automated contacts with their roving signals aren’t
too much of a problem so just do what you need to make the contact, but please leave the top part
of the passband for the operators using computer control.
AO-27
The Microsat buss structure, used in several digital satellites, proved to be very popular and
other satellites were built using it. One of these is AO-27. It even has a similar orbit, with an altitude
of about 793 kM and a period of 101 minutes. Unlike the Microsats, though, there are two factors
that make AO-27 unique: it is not dedicated to the Amateur Satellite Service, and it is an FM crossband repeater. AO-27 is actually an amateur payload aboard a commercial satellite known as
Eyesat-1, which runs experiments for Interferometrics, Inc. of Chantilly, VA, USA. To preserve
batteries and other demands on the satellite’s resources, AO-27 is not constantly “on” but rather
springs to life 18 minutes after entering sunlight over North America and remains on for 20 minutes. The control operators will let this schedule “drift” somewhat every few months, allowing more
southerly stations to take advantage of the repeater. The satellite presently is operating in “power
mode 2”, which gives a signal of only approximately 600 mW but this is subject to change.
There are a few operating considerations with this bird that must be observed. First, the uplink
and downlink are both FM. This may not sound like a problem, but remember that FM is far less
efficient than SSB or CW. Although uplinks of 10 watts into a ground plane antenna will get you
heard, the downlink may suffer from deep fades if you don’t have a good receive setup. AO-27 is
18
another Mode JA bird, so you’ll be listening on 70cm and a good receive preamp is a must. If you
have a radio that allows tuning, the center frequency is 436.795 MHz, but don’t forget the effects
of Doppler Shift which will be +/- 10 kHz. If you have an FM only rig with 5 kHz steps, don’t worry;
just start listening high (about 436.805 MHz) and step down in frequency as the pass progresses.
Program your rig with the following frequency pairs.
Downlink
436.805
436.800
436.795
436.790
436.785
Uplink
145.845 AOS
145.850
145.850 Mid Pass
145.850
145.855 LOS
Second, as a repeater and not a transponder, only one person can talk at a time. The strongest
signal will be captured by the satellite’s receiver (just like on your local 2m repeater) and everyone
else will be shut out. Third, as I mentioned before, the satellite’s dual purpose use makes it available only when in sunlight and usually only when it is over North America (roughly North 74 degrees to North 5 degrees).
UO-14
UO-14 was originally used as a digital store and forward BBS. It carried digital traffic around the
world for medical staff working in communication challenged third world countries. When UO-22
was launched it took over the duties. Since that time UO-14 had been sending telemetry until
February, 2000 when the control operators toggled the bird to mode J FM. UO-14 is currently
operating as an FM bent pipe “repeater” satellite. It is a full duplex bird, meaning you can listen to
the downlink as you transmit. UO-14 is similar to AO-27 with the exception that it is available for
use fulltime. The transmitter is a little more powerful than AO-27, so antenna gain and orientation
do not seem to be as critical.
You should program your radio with 5 frequency pairs for working UO-14. Start with the first pair
and tune to the next one as the pass progresses.
Downlink
435.080
435.075
435.070
435.065
435.060
Uplink
145.970 AOS
145.975
145.975 Mid Pass
145.975
145.980 LOS
ARISS
ARISS is Amateur Radio on the International Space Station. This is a cooperative effort of many
countries to extend the very successful work done with Mir and SAREX aboard the Shuttle. Now
that the space station is inhabited full time, amateur radio activities have begun. The callsigns and
frequencies used are listed below:
RS0ISS - RZ3DZR (also TNC)
NA1SS - DL0ISS - ALPHA
145.800 MHz
145.990 MHz
145.200 MHz
144.490 MHz
Russian Module callsign
Other club callsigns
Worldwide downlink for voice & packet
Worldwide packet uplink
Region 1 voice uplink
Region 2 & 3 voice uplink
19
You may have noticed that there are two voice uplink frequencies. For North and South America,
use the Region 2 frequency of 144.490 MHz. A good place to keep up to date on ARISS is at the
official webpage at http://ariss.gsfc.nasa.gov/
Here are the QSL routes for stations working the International Space Station:
US Stations:
Margie Bourgoin, KC1DCO
Attn: ARISS Expedition-1 (or 2, 3) QSL
ARRL, 225 Main Street
Newington, Connecticut 06111
Canadian Stations:
Radio Amateurs of Canada
Attn: ARISS Expedition-1 (or 2, 3) QSL
720 Belfast Road, Suite 217
Ottawa, Ontario K1G 0Z5
European stations (a SASE and 2 IRC's are required to get a QSL in return):
AMSAT-France
14 bis, rue des Gourlis
92500 Rueil Malmaison
France
Make sure to check the ARISS web site for current QSL info. The expedition number will be
changing as the crews change. A self-addressed, stamped envelope is required to get a QSL in
return.
Several other exciting projects are in the works for the ISS. These include the popular SSTV
system that was used on Mir and other digital projects.
20
Working the Birds
You have probably heard someone make a statement that started “It goes without saying that...”
which, by its very nature, indicates that something should be said. When we are talking about
starting your satellite career, that “something” is this: Don’t be in a hurry, spend some time to
determine where you are in terms of experience and equipment (be honest), and think about what
you wish to achieve. Once you know these things, you will have a better understanding of how to
get started and what direction you will need to travel to reach your goals.
This is where I should be telling you about how easy and cheap it is to get onto the Amateur
satellites. Well, I can’t really do that. Is it easy and cheap? Yes, it is easy, and cheap is possible,
but like every other aspect of our hobby, you can spend as much money as you want. It’s just a
matter of what you feel comfortable with. The point is, though, you don’t have to spend a lot. You
may not need to spend anything if you already have a radio, because the first step is to just listen.
After that, your course is up to you.
First, take a look around your shack. What equipment do you already possess? Do you have a
radio or radios that are “satellite friendly”? If not, are you willing to spend the effort and money to
do so? Don’t worry; chances are that you have something right now that you’ve been using and
just never considered to be a part of an Amateur Satellite station.
At the risk of sounding trite, let me use a few more of those “old expressions” we often hear (and
ignore) because they accurately represent what I feel is the best approach to becoming satellite
active.
• First Things First - The best way to become involved is to listen. You don’t have to have anything other than a shortwave receiver, police scanner, or 2m FM handi-talkie to do this. These
aren’t ideal, but they can be used to hear the downlinks and will help familiarize you with some of
the basics: Determining passes and adjusting for Doppler shift. These will also give you an idea of
the various patterns of QSO’s to be found on the satellites which vary from one satellite to the next.
• Take It Easy - The reason I recommend starting with the Easy Sats is because they are, well...
EASY! You can gain valuable experience here without risking a fortune or becoming so confused
you quit and take up some other more mundane hobby. That doesn’t mean the Easy Sats are only
good as a starting point and should be abandoned later, either; some people start here and never
leave.
• One Step at a Time - Don’t feel compelled to assemble a full satellite station in a short period of
time. This will only lead to frustration as you spend more time wondering what to acquire next,
when you should really be enjoying what you have. Each upgrade should serve as a building block
for the next. Don’t be in a hurry. Relish the entire experience. Have fun!
Have a 2m Radio?
Once you have acquainted yourself with the satellites by listening, it’s time to start making contacts. Perhaps you don’t have an HF rig, but are equipped for 2m FM. In that case, consider trying
to work the ISS. If you also have a 1200 baud TNC, connect to the ISS BBS. Simple stuff, and
except that the other station is moving, not much different from your basic 2m operation. Just
remember that, whether you’re working voice or packet, the passes don’t last long and there may
be others wanting to do the same thing. Keep your contacts short, and if you’re on packet, send a
“disconnect” before you loose contact or it will be unavailable until its TNC retry count is exceeded
and the TNC resets. Don’t forget the effects of Doppler Shift; start listening high and tune down as
the bird passes.
21
Have an HF Radio?
Maybe you have an HF receiver or transceiver. If so, you already have the ability to copy the 10m
downlinks of RS-12 and RS-15. The antenna you use for the downlink will make some difference,
but use whatever you have; you might be surprised at how well you can pull in those signals from
space with what you have now. If you find that you are having some difficulty hearing the passes,
consider a receive preamp. At 29 MHz you can use one inside the shack, but a good practice is to
mount it close to the antenna where the signal is greatest. A word of caution is in order here: make
absolutely sure you don’t transmit through your preamp unless it is designed for transceiver operation; otherwise you end up with a very useless attenuator instead.
OK, so you’ve mastered the 10m downlink and are ready to take another step. If you are an
Advanced or Extra license holder, try RS-12 Mode K. To make easy contacts, it is helpful to have
a transmitter or transceiver for the 15m uplink and a separate receiver or transceiver for the 10m
downlink, although some Mode K operators use split VFO operation in a single radio by determining the downlink frequency and factoring in the proper shift. This works after a fashion, but as the
bird moves and the frequency changes, it can be really hard to maintain a QSO because one or
both of you are chasing the signal up and down the band. If you have a 2m SSB receiver or
transceiver, then operate Mode T (or KT if both are on).
Have Both?
If you have a means of generating a CW or SSB signal on 2m as well as a 10m receiver, then
you’re ready to get on the Mode A satellites, RS-12 and RS-15. If you don’t yet have a 2m multimode transceiver, you may want to consider getting one. The reason I suggest the 2m multimode
is obvious if you’re interested in satellite work; it will get you onto not only RS-12 and RS-15, but
there are other birds where 2m transmit is necessary. Many hams, particularly the No-Code Technicians, start out with HT’s and eventually find they want to get something more. The 2m multimode at home will allow them to remain on their favorite repeater or FM simplex frequency while
trying something new. Besides, there is a lot of 2m DX to be worked on the low end of the band!
If you can generate the RF, chances are you can hit the bird. Don’t sweat it if you can’t afford a
big expensive new 2m base; there are used units to be found if you look. Some are mobiles, but
what does that matter? Have you heard the old saying “It’s not the age or size of the car that
counts, it’s how well you drive it”? Substitute “radio” and “operate” for “car” and “drive” and you’ll
get the idea. You won’t need a lot of power to communicate through the satellites. In fact, you’ll
need AT MOST 100W EIRP; it’s usually much less. Take into consideration the power out from
your radio, feed line and connector loss and antenna gain.
Note to my No-Code readers: Don’t worry that you don’t normally have access to the HF bands.
You aren’t transmitting on 10m, the satellite is, and the sponsoring group is responsible for meeting the licensing requirements for HF. Think of it as using someone else’s station.
All We Need Now is 70cm
So far we’ve looked at the equipment needs for using ARISS, RS-12 and RS-15. Let’s discuss
UO-14, FO-20, AO-27 and FO-29. Access to these four requires only one more thing: a way to
receive the 70cm downlink. This means you’ll need either a 435 MHz capable receiver/transceiver
or a converter with your 10m receiver/transceiver. If you go the latter route, bear in mind that the
satellite allocation on 70cm goes from 435 MHz to 438 MHz. This really isn’t a problem if your HF
radio has general coverage capability, but if it doesn’t you will need a converter that has selectable
local oscillators. That will allow you to have, for example, one position that converts 435 - 436.7MHz
22
and the other 436 - 437.7 MHz to the standard 28 - 29.7 MHz 10m band. If you use a converter,
you can save money by mounting the converter at the antenna instead of using a preamp because
most converters have plenty of output gain to help overcome line loss at 10m. Finally, heed the
warning I gave you previously: DON’T TRANSMIT THROUGH YOUR CONVERTER OR PREAMP!
(That’s twice. Don’t say you weren’t warned.)
That’s All, Folks!
Well, what do you know? We’ve covered all the Easy Sats! Pretty painless, wasn’t it? If you
already had some or all of the necessary equipment it didn’t cost too much either. The really great
part is that you are now an Amateur Satellite Operator and, with the addition of just a little more
equipment, you can work the rest of the Amateur satellites, too. Keeping with the concept of the
Easy Sats, I won’t go into detail on this but if you’re really interested, read “More Boxes, More
Sats” coming up next.
23
More Boxes, More Satellites
Even though the intention of this paper is to introduce the reader to the Easy Sats, there are
other types of satellite operation that I feel I should mention. Although they don’t quite fit the criteria
of “easily used” put forth in my introduction, and they will add some cost to your satellite station,
many hams will want to progress upward and we can’t leave these out.
The Mode JD Satellites
Another mode, in fact the last one available on the LEO’s, is Mode JD. As you may have guessed,
the “D” stands for Digital and there are two different sub-modes based on the data rate. At present
you have the opportunity to work 1200 baud, which requires one more piece of equipment, or 9600
baud, which may require simple modifications to your radios.
The easier of the two is the former, 1200 baud, and for this we have available AO-16 and FO-29.
The added piece of equipment is known as a PSK modem and is attached outboard to your TNC.
If you are lucky enough to have one of the multimode TNC’s now available you have one already.
I say this is the easier of the two because it is basically a matter of “plug and play”; attach the
cables and you’re ready. Notice that the PSK downlink is a SSB mode, so you’ll need a receiver
capable of SSB reception. Remember that since the bird is moving you’ll experience the phenomenon of Doppler Shift. By design, most PSK modems have the ability to change the received
frequency using the frequency step functions built into the microphone connector of many modern
radios.
Using the 9600 baud birds (UO-22, KO-23, KO-25, TO-31 and UO-36) might require modifications to the transmit and receive circuitry of your radios for the same reasons that apply to terrestrial high speed links. Simply put, until the recent appearance of radios specifically designed to
handle the increased throughput, all signals were routed through the microphone and speaker
connectors, and the waveforms at 9600 baud got distorted too much. What was required was
minor surgery to inject the audio after the microphone and pick it off at the discriminator. This was
no big deal on some rigs but caused many a headache on others and should to be considered
when you set up your Mode JD station. Some of the 9600 baud FM TNC’s will require that you
manually change frequency, too, or you can run a program that will do your radio tuning. It’s a bit
harder if done by hand, but if you keep an eye on the DCD LED, you will be OK. It takes a little
practice, but it can be done. By the way, this is another reason to be careful in the selection of your
receiver; FM-only radios usually tune in 5 kHz steps and that is just too great a jump to stay locked
on to the signal for digital work, although for analog contacts it will usually be ok.
One final word on working digital satellites is in order. Once you have all of your equipment on
line, you will need a way of talking to the satellites or you won’t get anywhere. FO-29, when it is in
digital mode, is actually not much harder to access than your local packet BBS. Using your favorite
packet program, just change a few of the TNC’s parameters and connect to 8J1JCS. That’s it!
Don’t forget to disconnect before you lose the signal, though.
Most of the present Mode JD digital birds operate in the “store and forward” mode. You upload
your messages or files and they get stored until someone else asks for them. To do this correctly,
your modem must be capable of KISS operation, and you will need a suite of programs named
“PB/PG” (for DOS) or WiSP (for Windows). I got on these satellites with WiSP, a really slick piece
of work available on the AMSAT web site. Note that this isn’t freeware; it is shareware and is
registered with AMSAT. It is quite amazing sitting back watching the broadcasts scroll across the
screen, hearing your 2m rig key up, and seeing your call pop up in the queue.
24
If digital satellite work interests you but you aren’t sure that your interest is sufficient to warrant
the added expense of a PSK or 9600 baud modem, there is a way to try out these modes using
only your computer and land-line modem. There are stations, known as SatGates or Satellite
Gateways, that consist of a digital satellite station connected to a land-line BBS. Using these,
anyone can call in and have a look at the currently available directories and files that reside on
whichever satellite the SatGate is configured to operate. In addition, most SatGate operators,
upon confirmation of a users valid Amateur Radio license, will issue the caller a password that
allows uploading of files and messages to the satellite. Operation in this manner isn’t as “real time”
as a sitting in front of your computer during an actual satellite pass but, since digital birds operate
as “store and forward” file servers anyway, this isn’t a big inconvenience.
Mode B on AO-10
Let us now look at the last Amateur satellite (AO-10), and the last common mode of operation
(Mode B). If you prefer to talk with people using your mouth instead of your fingers, this is a perfect
excuse for buying a 70cm transceiver or transverter instead of just a receive converter. Don’t think
I’m bad-mouthing CW, either; you can find it here, too. Just don’t expect to find packet. This bird is
presently the “big boy” of the Amateur Satellite program, the only Molniya satellite since AO-13 reentered the atmosphere in December, 1996. It has a high orbit and is available for hours at a time
so once you are set up to work Mode B, you just sit back and start making contacts. As a result of
an unfortunate collision with part of its launch vehicle, AO-10’s high-gain antenna was damaged
and all transmission and reception is now done through lower gain omnidirectional antennas.
Later, AO-10’s on-board computer suffered a shutdown due to radiation damage and the orientation of the spacecraft is no longer controllable. Finally, some of the batteries have failed so, unless
the satellite is receiving a lot of sunlight, its power system problems will take it out of service. As a
result, if you are using AO-10 and you notice that the downlink is FMing, please cease operations
immediately. If the power supply gets too low, what is left of the on-board control may reset with
unknown and possibly fatal results. (Once when this happened, the nonfunctional high-gain antennas were reconnected. Only with great effort was the control team able to recover and switch back
to the omnis.)
You won’t have much luck working AO-10 with your LEO antennas; it’s just too far away and the
signal strengths too weak, although some people report success by working it when it is close to
the horizon and somewhere near perigee. (The satellite is moving very quickly during perigee and
behaves much like the LEO’s so the resultant Doppler shift is quite high. Take into account that the
transponder is inverted so you are “correcting backwards”, you can see how difficult this may be.)
Common uplink antennas include 44 elements (two 22 element beams crossed at right angles to
each other and fed 90 degrees out of phase to get a circular polarization) and helixes, which by
design also are circularly polarized. Common downlink antennas are similar to the uplink antennas
except the crossed beams are usually 22 elements.
You may be asking yourself why you should even bother equipping your station with directional
antennas or a 70cm SSB/CW transmitter when they are only used for AO-10. There are two big
reasons, and one of them can actually be a benefit for using the Easy Sats. First, and of immediate
importance, is that the same directional antennas you use for Mode B can also be used for Mode
JA and JD, increasing the efficiency of your transmitting and receiving systems. The 2m antenna
will also be useful for your Mode A uplink and Mode T downlink. When there’s no satellite available,
you’ll find those directional antennas really enhance your terrestrial work, too. The second reason
is that you’ll really want to work AO-40 after it’s launched, and this equipment will be necessary.
(AO-40 is also equipped with 1.2 GHz, 2.4 GHz and higher subsystems, but that’s well beyond the
scope of this paper.)
25
Auto Tracking and Tuning
Although not necessary for Easy Sat communications, there are controllers available that will
attach to your computer and tune your radios for you. (Assuming your radio is compatible with
such equipment. Many newer rigs are.) These are an added expense, and need only be considered if you decide to take the plunge and get into satellite communications in a big way. Most of
these controllers will also interface to your antenna rotor. Taking input from a tracking program, the
controller/tracker hardware will do all of the tuning and pointing, freeing the operator to concentrate on making contacts. Properly set up, one of these tuner interfaces can overcome the 9600
baud Doppler shift problem, too. Keep this in mind when you pick a tracking program. Almost all of
the popular tracking programs can talk to the majority of the hardware through TSRs and standard
system calls, but not all have this capability. Check before you buy.
Well, there you have it. We have now had a look at all of what is available for the Amateur
Satellite operator. Some of these, the Easy Sats, we discussed in detail. The remainder we looked
at briefly. We call the Easy Sats by that name for a reason: they are easy to use. Once you have
mastered these, there is plenty more to accomplish in your new career as an Amateur Satellite
operator. What I have offered is but one possible upgrade path; there are others. Whatever you
decide, it’s up to you. Good luck and have fun!
26
After the QSO: QSL Cards, Grid Squares and Certificates
It has long been said that “The QSL is the last courtesy of a contact” and this is just as true when
operating through the satellites as it is when we make any other QSO. Although not required, and
often shunned as antiquated or “too expensive” with today’s often rising postage rates and the
cost of getting cards printed, there is nothing quite like a wall of cards to remind you of past
conversations, long and short, with those other like-minded folk who share a common interest in
satellite communication.
The “too expensive” argument can be quite persuasive for some people, but there are ways to
help keep costs down. For starters, don’t feel that you have to take the concept of a fancy preprinted card as gospel; many people print their own on their home computers, and a printed or
handwritten sheet with the required contact-confirming information is just as valid as a slick fourcolor printed piece of cardboard. They aren’t as fancy, but they’re just as valid for our needs.
To help keep postage costs down, consider using one of the many available QSL Bureaus. The
two most popular for satellite operators in the United States are run by AMSAT and the ARRL, but
there are others, some commercial and others voluntary. These Bureaus, working in conjunction
with their counterparts in other countries, will accept your cards (properly sorted by whatever
standards they require), merge them with cards from other hams going to the same country, and
forward them in bulk. The receiving Bureau will take these cards, sort them out by call sign, and
deliver them to their final destination. This process may take a while, so please be patient. Many
other countries don’t enjoy as efficient a mail system as we do and it may take months or even
years for your card to get there, or for cards you are expecting to reach you.
Just how does the bureau system work? For the North American satellite operator, the AMSATNA Bureau is the way to go, and it works like this:
For outgoing QSL’s, arrange your cards alphabetically by call sign and send them to
AMSAT QSL Bureau
c/o Walt Rader WA3DMP
3702 Allison Street
Brentwood, Maryland 20722
Cards sent within the US are free and cards going out of the country are $0.10 each.
To receive cards from the bureau, send several #10 envelopes with one unit postage to the same
address. Print your callsign in the upper left corner. All mailings are sent at the end of the month
and you will get yours within a few days after that. If you are patient enough to wait until a few cards
have arrived before your envelope is sent, immediately under your callsign on the envelope write
the number of cards that should accumulate before being sent. Don’t forget to keep track with how
many envelopes you have left at the bureau; cards not sent out after six months are destroyed.
One difference between the cards we send and receive on the satellites and those for HF QSO’s
is the inclusion of the Grid Square, a set of four or six characters that define just where on Earth we
are located. The use of Grid Squares, or more correctly the Maidenhead Grid Square Locator
System, grew out of the older QRA system used in Europe that was developed to give some
challenge to making contacts using the short range VHF and UHF equipment of the day. When
ranges for contacts on these frequencies began to increase with improvements in equipment and
more operators, it was discovered that the QRA coordinates could be duplicated in locations outside of Europe.
27
A conference was held in Maidenhead, England and the entire planet was divided into a grid of
324 large areas, or Fields, each covering 10 degrees of latitude by 20 degrees of longitude. Each
of these Fields was further divided into 100 Squares of 1 degree by 2 degrees. This is where we
get the name Grid Squares. Each is denoted by a two-letter/two-number combination in the format
XXYY, where XX is one of the 324 fields and YY is one of the 100 grids within that field. For
example, Raleigh, North Carolina is located in Grid Square FM05, but so are several other nearby
towns. To further help pinpoint locations, many operators will take advantage of a third designation
(zz) appended to the grid square that is the result of breaking the grid square into sub-squares of
5 minutes by 2.5 minutes. Using the full six character locator will usually give an indication of less
than a few miles of where a station sits. My complete Grid Square, based upon my geographical
coordinates, is FM05pp. In fact, I’m the only Ham that can make that statement! If you live in a
sparsely Ham-populated area, you might be able to make a similar claim.
So what do we do with this magical information? We put it on our QSL cards, that’s what, and
hope other satellite operators do the same. It may seem like just another bit of extraneous information now, but when we talk about Certificates and Awards later, you’ll see the importance.
How do you go about finding out which Grid Square you are in? There are several ways of doing
this. The most obvious method is to find a local Satellite or VHF/UHF operator and just ask. If that
isn’t possible, buy or borrow a copy of the ARRL published Grid Square Map or reference book
which lists many domestic and foreign locations and their Grid Squares. This won’t give you enough
precision to determine your sub-grid but it will meet the requirements of knowing which grid you
are in. If you can’t find out your Grid Square either of these ways, perhaps you can find what your
geographic coordinates are and plug them into one of the many available conversion programs. It
wouldn’t hurt to know this information anyway; you’ll need it to set up whatever tracking program
you will be using. (In fact, if you’re filling out a QSL, you’ve already made at least one contact, and
unless you just happened to turn on your radios and heard a pass in progress, you’ve already
configured your tracking program.) Other methods to consider are the use of topographical and
street maps, CD-ROM based trip routing software, and even getting a fix with a Global Position
System (GPS) receiver.
Now that you know your Grid Square and have it on your QSL card, what other benefit is this
information? First and foremost, it’s because other satellite operators will be giving you theirs and
requesting yours. But why, you may ask? Like other aspects of Amateur Radio, there are certificates and awards available for the satellite operator and one of these, the VHF/UHF Century Club
award from the ARRL, is very popular. The VUCC, as it is often called, was created as an incentive
for HAMs to populate the VHF and UHF bands and recognizes the successful completion of contacts with other Amateurs in at least 100 different Grid Squares, with endorsements for each
additional 25 Grids worked. The basic VUCC award stipulates that these contacts be made on a
single band from six meters and up, but there is a Satellite Endorsement which counts ALL satellites (even RS-12 with its 15m up/10m down configuration) as one band. Achieving satellite contacts from 100 different Grid Squares isn’t hard, either, for an operator who puts in a little effort.
What about those cards that come in that don’t have the Grid Square on them? Do you just
discard them and hope you work someone in that Grid at a later date? Not necessarily. The requirements for the VUCC only stipulate that you make a concerted reasonable effort to determine
the Grid Square. This can include looking up the location on a map, writing them a letter, calling on
the phone, or just about anything else. This is another good reason to have a collection of maps,
but if you want to keep the stack of maps to a minimum, consider one of the trip routing CD-ROMs
mentioned earlier. Just make sure that whatever CD-ROM you buy will output coordinates; not all
do and cost isn’t a good indicator of how well they will serve our nontraditional purpose. I have two
that I use and neither cost me over $30.
28
Aside from the VUCC, there are a number of other certificates that are popular. Another, although not specific to the satellite program and lacking any endorsements for us, is the ever
popular Worked All States from the ARRL. Believe it or not, it isn’t as easy as it may sound,
particularly on the LEO’s. Look at the footprint of any satellite during a typical pass and, with the
exception of RS-15, you’ll see that only a portion of the country is covered. This can be a real
challenge for operators on either coast and often pulling in those last few (and hoping they get
confirmed) can be a time consuming frustrating project.
All of this sounds very interesting, but what about AMSAT? Don’t they offer any awards or certificates? They are, after all, the satellite folks and you would think that they would offer something to
help promote the program, wouldn’t you? Yes, you would, and you would be right. AMSAT offers a
number of certificates, ranging from the Satellite Communicators Club available for making just
one satellite contact, through the K2ZRO Memorial Station Engineering Award given out for participating in a difficult test of station receiving capabilities, to the W4AMI Satellite Operator Achievement Award for making at least 1000 contacts with any station on any satellite. Other awards
include, but are not limited to, the OSCAR Satellite Communications Achievement Award, the
OSCAR Sexagesimal Award and the OSCAR Century Award given for proof of contact with 20, 60,
or 100 different U.S. or Canadian call areas or DXCC countries.
Any others? Sure, but the list is growing constantly, so the best bet for the Satellite Award Hunter
would be to contact AMSAT and the ARRL for further details. Address and phone numbers for both
can be found in the section “My Resources” near the end of this paper. An updated list of most
known satellite certificates and awards is printed occasionally in The AMSAT Journal, the official
publication of AMSAT-NA.
29
“How One Ham Got On the Satellites”
Theory is nice, but it’s application that really counts so, if you’ll indulge me, I’ll tell you a bit about
my satellite setup and some of the successes (and failures) that I’ve had.
For pass prediction/tracking I have three favorite programs that I run on my 386SX PC. The first
program I use is called AOS_US, which is out of Germany and distributed as freeware, but the
user is encouraged to make a small donation to AMSAT-DL to benefit their Phase 3D fund raising
effort. I like this program because I can feed it a Keplerian Element file tailored to my operating
needs and it will create a listing of pass opportunities for all the satellites I use. The listing can be
for an almost unlimited length of time and can be sent to a disk file or directly to the screen. I also
appreciate how AOS_US allows me to generate one file for all of my satellites of interest. I can
then print this out and keep it near my operating position for quick referral.
My second pass predictor is called STSOrbit Plus. This piece of shareware will allow you to
visually track up to 30 satellites at a time on a graphical display, resembling NASA Mission Control’s
“big board.” My favorite part of this is the “multiple satellites at once” display which allows me to
visually see where all of my favorite satellites are at one time and watch as they progress in their
orbits. STSOrbit Plus will run without a coprocessor, but having one really helps.
My last pass predictor is InstantTrack. It will graphically plot only one satellite at a time, but its
code is tight and the program is FAST! IT is a natural for running on older AT style machines
because it just doesn’t need the horsepower required by a lot of the newer programs.
(I do use other software, including NOVA for automatic radio control and WiSP for digital satellite
communications, but I won’t discuss those here. More information on these and other software
packages available through AMSAT can be found in the Software handout available from AMSAT
HQ. See the section on AMSAT later in this paper for the address and phone number.)
Now let’s talk about the hardware.
For Mode K: (RS-12)
Transmitter: 15m up Kenwood TS-690S
Transmit antenna: Dipoles, one oriented E-W, one N-S.
Both at about 6 meters.
Receiver: 10m down Uniden HR-2600
Receive antenna: Turnstile at 4 meters
This setup works very well. The Uniden was pressed into service when an older HF rig I was
using bit the dust. The front end is a bit wide, and I can hear my uplink desensing the receiver a
small amount, but once the bird is up over about 15 degrees, copy is no problem. In the first month
of operation on this satellite I worked 28 states.
For Mode T: (RS-12)
Transmitter: 15m up Kenwood TS-690S
Transmit antenna: Dipoles, one oriented E-W, one N-S.
Both at about 6 meters.
Receiver: 2m down Yaesu FT-736R
Receive antenna: Eggbeater at about 5 meters
I was very pleasantly surprised when RS-12 was switched to Mode KT and I had the opportunity
to try out the 2m downlink. The biggest impression I had was that the signals seemed much
stronger than those on 10m. At first I thought this might just be due to my particular antenna and
receiver combination, but conversations with others saw many of them expressing the same opinion. Be warned, though, that it is quite possible for one person in a QSO to be listening on 10m
30
and the other person to be listening on 2m, so if both people are not tuning their receivers (per
standard practice), then the whole conversation will become a matter of signal chasing. I quickly
discovered this and learned to compensate accordingly. Even then, I found it best just to keep the
other person tuned in even if it meant my own signal came back to me “off frequency” or disappeared all together.
The first thing you might notice is the FT-736R. This Multiband Multimode radio, although recently discontinued, can be found used. It still can cost quite a bit, but don’t be alarmed. It isn’t
necessary to run out and spend big bucks to work Mode A. I sometimes use a Kenwood TM-255A,
a multimode mobile I bought a while back, and I have also used a TS-700 and IC-251A, both old
and affordable. The reason I upgraded was because the TM-255A is usually in the truck, I sold the
TS-700, the Icom had a few proprietary parts in it that decided it was time to fail, and a newer radio
was affordable at the time. Listen to a few passes and hear what folks say they’re using. You might
be surprised.
You may not recognize the Eggbeater. This is manufactured by M2 (M Squared) and consists of
two vertical loops that are oriented at right angles and fed 90 degrees out of phase. This produces
a somewhat omnidirectional pattern in the horizontal plane that becomes circularly polarized as
you pass over head. The entire pattern looks somewhat like a hemisphere that has had the top
depressed a bit. I got the Eggbeaters because I wanted an uplink antenna that wouldn’t need to
follow the satellite as it passed over and had minimum nulls. I bought one for 2m and one for 70cm,
and I don’t regret having them, but think I could have had just as good performance at lower cost.
My first 2m antenna was one of those creations made from a mobile 5/8 wave on a ground plane.
It was my original satellite antenna but suffered from an unexpected impact with the ground. (dropped
it from the roof accidentally. OOPS!)
For Mode A: (RS-12, RS-15)
Transmitter: 2m up Yaesu FT-736R
Transmitter antenna: Eggbeater at about 5 meters
Receiver: Kenwood TS-690S
Receive antenna: Same as Mode K
How does this setup work? Very well. I’ve been on Mode A for a while now and have worked over
30 states. The QSO’s number well over 150. (You start to hear some of the same calls. After the
newness wears off you actually start having conversations with these fine people. I can recognize
many by voice now, even if they’re not quite on frequency.)
For Mode JA: (FO-20, AO-27, FO-29)
Transmitter: 2m up Yaesu FT-736R
Transmit antenna: Eggbeater at about 5 meters
Receiver: 70cm down Yaesu FT-736R
Mirage KP-2 Mast Mount Preamplifier
Receive antenna: Eggbeater at about 5 meters
The only new equipment here is the preamplifier, and the 70cm version of the Eggbeater. Following common practice I have the preamp mounted directly below the antenna with the +12 volts
needed by the preamp supplied by way of the feedline. A module inside the shack couples the
voltage to the line which is then picked off by the preamp. This is a good arrangement as it requires
no additional lines be run and the preamp can be controlled remotely. Like many new preamps on
the market, there is also an RF sensor built in which will switch the preamp out of line during
transmit. As an option, preferred by many, the +12 can be removed by applying a signal from the
transmitter’s PTT line.
31
My success on Mode JA is not nearly as good as on the other modes, but of the three, I seem to
be having more luck on FO-20. I have several contacts under my belt but I still fall victim to
correcting in the wrong direction like I mentioned earlier and wind up frantically trying to reacquire
my own signal. There is also a problem with polarization differences between the Eggbeater and
the FO- satellites. The Eggbeater has Right Hand Circular Polarization but FO-20 and FO-29, with
their antennas mounted so they spin around the satellite’s axis of rotation, seems to have a signal
that is Left Hand CP for the first half of the pass. If you remember that there is a substantial crosspolarization penalty, you can see how a marginal signal will simply disappear.
My AO-27 contacts are even fewer and I seem to get a lot of quick fading. I can’t even hear my
downlink until the satellite is above about 50 degrees elevation, so I’m probably being blocked by
my surroundings and I am confident that raising the Eggbeater for a better view of the sky would
help a lot. I have also noticed the problem common to FM birds where one or two strong stations
tend to monopolize the repeater.
I think a little antenna work will help greatly. Still, I am making contacts and having fun on Mode
JA. Ultimately, I want to upgrade my system to include directional antennas and automatic control.
By the way, I use this same setup on Mode JD with great success, but the digital nature of that
mode helps substantially.
Incidentally, before buying the FT-736R I used a receive converter with my TS-690S for the
70cm downlink. Translating the displayed frequencies was a minor task, but it worked. Before
learning how to operate the Yaesu’s “Satellite Mode”, I even used the TM-255A on the uplink and
just used the FT-736R as a receiver. Don’t feel you have to use a special radio designed for
satellite operation; what you have or what you can afford will be fine.
Am I satisfied with my satellite abilities? Yes and No. Yes, I am, because I’m having a lot of fun
with what I have, I’m making contacts almost daily (I do have other interests and obligations), I’m
making new friends, and I’m taking part in the future of Ham Radio. No, because I know that there
is more, and I sometimes get impatient. Ah, well, there is always tomorrow, isn’t there? I think I’ll
save some challenges for then.
32
My Resources
When I started in my Amateur Satellite career, as with many activities in which I partake, the first
thing I did was read. We are fortunate that there are many good sources of information available,
and I found the following to be invaluable. I referenced these often while researching this paper,
but I must warn you that these are just “the tip of the iceberg”. Any questions that I couldn’t answer
by reading were quickly addressed by posting my queries to the AMSAT-BB (see below).
A greatly expanded version of this section is available from AMSAT HQ as the handout “The
Amateur Satellite Resource Guide”. I highly recommend obtaining a copy. In it you will find data
about more books, nets, World Wide Web, and ftp sites, magazines, newsletters and software
available through AMSAT.
Books
The AMSAT-NA Digital Satellite Guide, G. Gould Smith, WA4SXM, and others
Available from AMSAT HQ. An introduction to operating through the packet satellites, including the use of the DOS programs PB and PG and the installation and setup of WiSP.
Updated in 2001
The 2002 ARRL Handbook for Radio Amateurs, Paul Danzer, N1II, editor, satellite section
edited by Robert Diersing, N5AHD
Available from the ARRL and other sources. Although not totally devoted to satellite operations, the Handbook covers practically everything that an Amateur needs to know. Filled
with theory, applications and construction articles. A “must have” book. The Handbook on
CD contains sound files from several Amateur satellites.
The Radio Amateur’s Satellite Handbook, Martin Davidoff, K2UBC
Available from the ARRL, Amsat HQ and other sources. Previously titled the Satellite
Experimenter’s Handbook, this is considered by many to be “the book” on operating the
Amateur satellites. Contains the history of the program, theory, construction articles and
much more. This is the first edition, February 1998.
E-Mail Resources
AMSAT mailing lists
There are several of these, each with a specific purpose:
ANS - official AMSAT News Service bulletins.
AMSAT-BB - the AMSAT “bulletin board” list.
AMSAT-DC - Items of interest to AMSAT people in the District of Columbia area.
AMSAT-NE - Items of interest to AMSAT people in the New England area.
KEPS - Keplerian element distribution.
SAREX - Information on the SAREX project.
AMSAT-EDU - AMSAT Educational Liaison mailing list.
Send E-Mail to majordomo@amsat.org with the word “help” in the body of your message
for instructions on using the automated mailing list server.
33
ARRL Mail Server
Send an E-Mail message to info@arrl.org. In the message body, put “send index” (new
line) “quit” (both without quotes). You will receive the most recent index of all files available
on the Server. Be warned that the index is large and will be sent in two parts. There are
several good text files here on working the satellites, as well as information on many other
topics.
World Wide Web Resources
http://www.amsat.org/
The World Wide Web AMSAT-NA connection. Has information on AMSAT, articles, photos,
and a link to the AMSAT ftp site for downloading software. This is the best place to start
when looking for amateur satellite information, especially on AO-40 and has links to other
sites.
http://www.arrl.org/
Home page of the American Radio Relay League. Contains lots of information on becoming a radio amateur, plus links to sites for practically any amateur related activity. Also has
links to ftp servers for downloading software.
http://www.muenster.de/~welp/sb.htm
A comprehensive site listing software available for digital modes that run on Sound Cards.
Modes available include SSTV, PSK31, Hellschreiber and more.
http://www.tbs-satellite.com/tse/
Looking for information on virtually any satellite in orbit? Check out the Satellite Encyclopedia online. Under Satellite, select TSE.
http://ariss.gsfc.nasa.gov/
The International Space Station (ARISS) web site.
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AMSAT
No discussion of the Amateur Satellite Service would be complete without a mention of AMSAT,
the world wide organization of Amateur Satellite operators and supporters. AMSAT, or the Radio
Amateur Satellite Corporation as it is officially known, is an almost entirely volunteer group, with
the few paid employees being limited to office staff. (AMSAT-NA has but one, our tireless office
manager Martha “Martha@amsat.org”, without whom we’d be in big trouble. Thanks, Martha!)
Everyone else, from the President, through the Area Coordinators and down to the good people
who manage the booths at Hamfests, freely give of their time and efforts. Many of the most ambitious satellite projects to date have been sponsored by the various AMSAT organizations and are
funded entirely with contributions.
If you will take a few moments and go back to the section “My Resources”, you will see that many
of the books are published by AMSAT. AMSAT is a nonprofit organization and all moneys derived
from the distribution of these materials is channeled back into the program. Practically all of the
programs and literature available from AMSAT were donated by their respective authors. The few
that are commercial in nature are offered because they fill a need not otherwise available or
because their general excellence and value to the Amateur Satellite operator has already been
determined. Even with these, though, AMSAT does not make a profit; anything received above
their actual cost is kicked back into the operating fund.
Use of the Amateur Satellites is obviously not limited to members of AMSAT, but I heartily encourage everyone to consider joining. Membership includes the bimonthly magazine “The AMSAT
Journal.” To join AMSAT, for more information on their program, goods and services or to get the
name of your closest Field Operations volunteer, please contact:
Radio Amateur Satellite Corporation (AMSAT)
850 Sligo Avenue, #600
Silver Spring, MD 20910-4703
Phone: (301) 589-6062
Fax:
(301) 608-3410
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In Closing...
When I first started thinking about writing this paper, it was to be a brief history of how one Ham,
me, got onto the satellites. It just sort of grew. In the future, I hope to have both an expanded
version and one that is much more brief. You have made it this far; others may not. If I have
generated even a little interest in the Amateur Satellite program, then my efforts have met with
success. I did it; so can you!
In the way of legalities, I must tell you that AMSAT is a registered trademark of the Radio Amateur Satellite Corporation, a really great organization of which I am proud to be a member. Please
consider joining.
The information in the section “My Resources” has been greatly expanded into a companion
handout titled “The Amateur Satellite Resource Guide” and was first distributed by the AMSAT
folks at the 1996 Dayton Hamvention. This document is constantly being revised, so you may wish
to contact Martha at AMSAT HQ and ask for the latest copy, or visit the AMSAT Web site.
I’d like to thank Barry Baines WD4ASW, Paul Williamson KB5MU and Mike Seguin N1JEZ for
proofreading this paper in its many incarnations, providing even more encouragement and not
laughing too loudly at my obvious errors of spelling and style.
Well, I guess that about does it. You may remember that I said I don’t know much about AO-10.
That is my next goal. I’m learning now and the great thing is I already have most of my station
assembled for Mode B! I can generate a 70cm signal so I just need to work on my antennas. Then
maybe get some rotators. Then an auto-steering box. Then... Well, you can see where this is
headed. I’m also looking forward to using AO-40, which should prove to be much easier to work for
lots of people owing to its various available modes, sensitive receivers and increased output power.
I truly hope to see you on the birds soon. And please, if you hear someone calling “CQ Satellite
from Whiskey Alpha Four Yankee Mike Zulu, Fox Mike Zero Five, North Carolina”, give me a call.
I’d love to hear from you.
Gary B. Rogers WA4YMZ FM05pp Apex, NC wa4ymz@amsat.org
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