RF Technology Eclipse Series Operating instructions

Eclipse Series
RF Technology
rfinfo@rftechnology.com.au
February 2005
R350/R500 Receiver
Operation and Maintenance Manual
This manual is produced by RF Technology Pty Ltd
10/8 Leighton Place, Hornsby, 2077 NSW Australia
Copyright ©1998, RF Technology
CONTENTS
CONTENTS
Contents
1
Operating Instructions
1.1 Front Panel Controls and Indicators
1.1.1
Mon. Volume
1.1.2
Mon. Sq.
1.1.3
N. SQ
1.1.4
C. SQ
1.1.5
Line
1.1.6
Power LED
1.1.7
SQ LED
1.1.8
Alarm LED
5
5
5
5
5
6
6
6
6
6
2
Receiver Internal Jumper Options
2.1 JP1: 240Hz Notch Filter
2.2 JP2: Audio Response
2.3 JP3: Audio Filter In/Out
2.4 JP4: 600Ω Line dc Loop COS
2.5 JP6: COS Polarity
2.6 JP7, JP8, JP9: dc Loop COS Configuration
2.7 JP7, JP8, JP9: Direct Output COS
2.8 JP11 EPROM Type
2.9 JP13: Squelch Defeat (pcb 30/9131/0004 or later)
2.10 JP19: LED Alarm output (pcb 30/9131/0004 or later)
7
7
7
8
8
8
8
9
9
9
9
3
Receiver I/O Connections
3.1 25 Pin Connector
9
9
4
Frequency Programming
9
5
Circuit Description
5.1 RF Section
5.2 IF Section
5.3 VCO Section
5.4 PLL Section
5.5 Audio Signal Processing
5.6 Noise Filter, Amplifier and Detector
5.7 Subtone Filter and CTCSS
5.8 Microprocessor Controller
5.9 Carrier Operated Switch
5.10 Voltage Regulator
11
11
11
12
12
13
13
13
14
14
14
6
Alignment Procedure
6.1 Standard Input Signal
6.2 RF Alignment
6.3 IF Alignment
6.4 Line Level Adjustment
6.5 TCXO Calibration
14
15
15
15
16
16
Page 2
RF Technology R350/R500
CONTENTS
CONTENTS
7
Specifications
7.1 General Description
7.1.1
Channel Capacity
7.1.2
CTCSS
7.1.3
Channel Programming
7.1.4
Channel Selection
7.1.5
Microprocessor
7.2 Physical Configuration
7.3 Front Panel Controls, Indicators and Test Points
7.3.1
Controls
7.3.2
Indicators
7.3.3
Test Points
7.4 Electrical Specifications
7.4.1
Power Requirements
7.4.2
Frequency Range and channel Spacing
7.4.3
Frequency Synthesizer Step Size
7.4.4
Frequency Stability
7.4.5
Nominal Antenna Impedance
7.4.6
IF Frequencies
7.4.7
Sensitivity
7.4.8
Selectivity
7.4.9
Spurious and Image Rejection
7.4.10
Intermodulation
7.4.11
Modulation Acceptance BW
7.4.12
Noise Squelch
7.4.13
Carrier Level Squelch
7.4.14
Receiver Frequency Spread for -1dB Degradation
7.4.15
Receiver Conducted Spurious Emissions
7.4.16
Audio Frequency Response
7.4.17
Audio Output Level
7.4.18
Audio Distortion
7.4.19
Channel Select Input / Output
7.4.20
Carrier Operated Switch Output
7.4.21
CTCSS
7.4.22
External Squelch Input
7.5
Connectors
7.5.1
Antenna Connector
7.5.2
Power and I/O Connector
7.5.3
Test Connector
16
16
16
16
17
17
17
17
17
17
18
18
18
18
18
19
19
19
19
19
19
19
19
20
20
20
20
20
20
20
21
21
21
21
23
23
23
23
23
A
Engineering Diagrams
A.1 Block Diagram
A.2 Component Overlay Diagram
A.3 Jumper Link Positions
A.4 Jumper Link Description
23
23
23
23
23
B
Parts List
27
RF Technology R350/R500
Page 3
1
OPERATING INSTRUCTIONS
WARNING
Changes or modifications not expressly approved
by RF Technology could void your authority to
operate this equipment. Specifications may vary
from those given in this document in accordance
with requirements of local authorities. RF
Technology equipment is subject to continual
improvement and RF Technology reserves the right
to change performance and specification without
further notice.
1
Operating Instructions
1.1 Front Panel Controls and Indicators
1.1.1
Mon. Volume
The Mon. Volume control is used to adjust the volume of the internal loudspeaker and
any external speaker connected to the test socket. It does not effect the level of the
600Ω line or direct audio output.
1.1.2
Mon. SQ.
The Mon. Sq. switch allows all squelch functions controlling the monitor output to be
disabled. This can be useful when you are trying to trace the source of on-channel
interference.
1.1.3
N.SQ
The N.SQ trimpot is used to set the noise squelch sensitivity.
procedure to set the noise squelch to maximum sensitivity.
Use the following
1.
Turn the adjustme nt counter clockwise until the squelch opens as indicated by
the SQ LED.
2.
In the absence of any on channel signal, turn the screw clockwise until the SQ
LED goes off. Then turn the screw one additional turn in the clockwise
direction.
Page 4
RF Technology R350/R500
1.1
Front Panel Controls and Indicators
1.1.4
1 OPERATING INSTRUCTIONS
C.SQ
The C.SQ trimpot is used to set the carrier squelch sensitivity. Carrier squelch is useful
at higher signal levels than those at which noise squelch can be used – typically from
1-200µ V input.
It is provided mainly for use in fixed link applications where a high minimum signal to
noise ratio is required or where very fast squelch operation is required for data
transmission. The carrier squelch will open and close in less than 2~ms.
In most base station applications carrier squelch is disabled by turning the adjustment
counter clockwise.
The carrier squelch may be set to a predetermined level as follows:
1.
First turn the adjustment fully counter-clockwise.
Then set the noise squelch as above.
2.
Connect a source of an on channel signal with the desired threshold level to
the receiver's RF input.
2.
Turn the screw clockwise until the SQ LED goes OFF.
Then turn the screw back until the LED just comes ON.
1.1.5
LINE
The LINE trimpot is used to set the line and direct audio output level. It is normally set
so that 0dBm (775mV) with a standard input signal gives 60% of maximum deviation
at 1 KHz. The level can be measured between test socket pins 6 and 1 and set as
desired.
1.1.6
POWER LED
The Power LED shows that the dc supply is connected to the receiver.
1.1.7
SQ LED
The SQ LED comes on when the audio to the line and direct outputs is unsquelched.
The LED and squelch function are controlled by noise, carrier and tone squelch
circuits.
1.1.8
ALARM LED
The Alarm LED can indicate the detection of several different fault conditions by the
self test circuits. The alarm indicator shows the highest priority fault present. Receivers
using software issue 5 and higher use the cadence of the LED flash sequence to indicate
the alarm condition. Refer to table 1. Receivers using software
RF Technology R350/R500
Page 5
2
RECEIVER INTERNAL JUMPER OPTIONS
issue 4 and lower use the LED flash rate to indicate the alarm condition. Refer to table
2.
LED Flash Cadence
5 flashes, pause
4 flashes, pause
3 flashes, pause
1 flash, pause
LED ON continuously
Fault Condition
Synthesizer unlocked
Tuning voltage outside limits
Signal level below preset threshold (fixed link)
dc supply voltage low or high
External squelch is active
Table 1: Interpretations of LED flash cadence
Indication
Flashing, 8 per second
Flashing, 4 per second
Flashing, 2 per second
Continuous
Fault condition
Synthesizer unlocked
Tuning voltage outside 2-7 Vdc
Signal level below preset threshold (fixed links)
dc supply voltage low or high
Table 2: Interpretations of LED flash speed, for early models.
2
Receiver Internal Jumper Options
In the following subsections an asterisk (*) signifies the standard (Ex-Factory)
configuration of a jumper.
2.1
JP1: 240 Hz Notch Filter
JP1 allows the 240Hz notch filter in the normal audio path to be bypassed.
Condition
Notch Filter In
Notch Filter Out
2.2
JP2: Audio Response
Condition
750 uSec. de-emphasis
Flat response
Page 6
Position
1-2 *
2-3
Position
1-2 *
2-3
RF Technology R350/R500
2.3
2.3
2 RECEIVER INTERNAL JUMPER OPTIONS
JP3: Audio Filter In/Out
JP3: Audio Filter In/Out
JP3 bypasses the 300Hz high-pass filter and 240Hz notch filter if necessary.
Condition
Hi-pass, Notch In
Flat response
2.4
Position
2-3 *
1-2
JP4: 600Ω Line dc Loop COS
JP4 allows the dc return path through the output audio transformer to be broken, to
permit dc signaling via the audio pair of wires.
Condition
dc Loop Configured by JP7/8/9
dc Loop Not used
2.5
JP6: COS Polarity
Condition
Active on Signal
Active on No Signal
2.6
Position
1-2 *
2-3
Position
2-3 *
1-2
JP7, JP8, JP9: dc Loop COS Configuration
These settings are relevant when the Carrier Operated Switch (COS) signal is to be
used across the same wires as the audio. Refer to setting of JP4, in section 2.4. They
control the levels and connection into the audio balanced line circuitry.
Condition
Source +12 Vdc Loop
Free Switch Output
2.7
JP7
2-3
1-2
JP8
ON
ON
JP9
1-2 *
2-3
JP7, JP8, JP9: Direct Output COS
In this arrangement, the COS signal is taken via the separate COS+ and COS- outputs,
either with free (floating) output or with +12Vdc pull- up.
Condition
+12 Vdc Direct Output
Free Switch Output
RF Technology R350/R500
JP7
2-3
1-2
JP8
OFF
OFF
JP9
OFF
OFF
Page 7
4 FREQUENCY PROGRAMMING
2.8
JP11: EPROM Type
Condition
27C256
27C64
2.9
Position
2-3 *
1-2
JP13: Squelch Defeat (pcb 30/9131/0004 or later)
Normal squelch can be defeated with an active low signal at DB-25 pin 19.
Condition
Squelch operation normal
Squelch Defeat
2.10
Position
1-2 *
2-3
JP19: LED Alarm o/p (pcb 30/9131/0004 or later)
The LED alarm can be brought out to DB-25 pin 7 for ATI
Condition
No Alarm Output
Alarm LED connect to DB-25 pin 7
3
Position
1-2 *
2-3
Receiver I/O Connections
3.1 25 Pin Connector
The D-shell 25 pin connector is the main interface to the receiver. The pin connections
are described in table 3.
4
Frequency Programming
Channel frequency and subtone frequency settings are maintained in non-volatile
memory for each of the 100 channels. Channel frequency and subtone frequency
programming is most easily accomplished with RF Technology TecHelp/ Service
Monitor software. This software can be run on an IBM compatible PC and provides a
number of additional useful facilities. DOS and MS Windows versions are available.
TecHelp/ Service Monitor allows setting of the adaptive noise squelch threshold,
provides a simple means of calibrating the signal strength output and minimum signal
alarm.
TecHelp/ Service Monitor can be supplied by your dealer, distributor or by contacting
RF Technology direct.
Page 8
RF Technology R350/R500
4 FREQUENCY PROGRAMMING
Function
DC Power
Channe l Select
RS232 Data
600Ω Line Output
Signal
+12 Vdc
0 Vdc
1
2
4
8
10
20
40
80
In
Out
LineLine+
150Ω / Hybrid
Discriminator Audio
Direct Audio Output
Audio Ground
Sub-Audible Audio
Out
Carrier Operated Sw
Carrier Operated Sw
External Squelch
COS+
COSInput
Pins
1, 14
13, 25
21
9
22
10
23
11
24
12
15
2
20
6
7
19
18
17
5
4
Specification
+11.4 to 16 Vdc
Ground
BCD Coded
0 = Open Circuit
or 0 Vdc
3
16
8
Opto-coupled Transistor
Switch (10mA 30V max)
<1 Vdc to Squelch
>2 Vdc or open circuit to
unsquelch
Logic1 = +5 to +16 Vdc
Test and Programming use
9600, 8 data 2 stop bits
Transformer Isolated
Balanced 0dBm Output
AC coupled, unsquelched
Direct AC Coupled Audio
Direct Audio Ground
Unsquelched, 1-250 Hz
Table 3: Pin connections and explanations for the main, 25-pin,
D-shell Connector
RF Technology R350/R500
Page 9
5
CIRCUIT DESCRIPTION
5
Circuit Description
5.1 RF Section
The following descriptions should be read as an aid to understanding the block and
schematic diagrams at the rear of this manual.
5.1
RF Section
A two section helical filter FL1 is used to limit the RF band width prior to the RF
amplifier transistor Q1. The output impedance of FL1 is matched to the input of Q1 by
C165, C1 and a microstrip line on the printed circuit board. Q1 is a very low noise
device with good intermodulation performance.
A four section filter consisting of FL2 and FL3 is used between Q1 and the mixer
MX1. This filter provides additional image and spurious frequency rejection.
The gain between the receiver input and the mixer input is approximately 10dB.
Monolithic amplifiers MA1, MA2 and transistor Q5 amplify the VCO output to the
necessary LO level for MX1.
MX1 is a high dynamic range double balanced mixer. The LO input level to MX1 is
approximately +13dBm the mixer conversion gain is approximately -7dB.
The network C7, C9, L1, L3 and R7 passes the IF frequency of 45 MHz and
terminates the RF and LO components.
The total RF section gain from J1 to the IF input is approximately 3dB.
5.2
IF Section
The first IF amplifier uses two parallel connected JFET transistors Q2 and Q3 to
obtain 12-15dB gain. The two transistors provide improved dynamic range and input
matching over a single transistor.
A two pole 45 MHz crystal filter XF1 is used
amplifiers. The second IF amplifier Q4 provides
pole crystal filter is used between Q4 and the 2nd
filters provide some adjacent channel rejection
frequency rejection.
between the first and second IF
additional gain of 6-10dB. A two
oscillator mixer. These two crystal
and all of the second IF image
U1 is a monolithic oscillator and mixer IC It converts the 45 MHz IF signal down to
455 kHz. The second oscillator frequency or 45.455 MHz is controlled by crystal Y1.
The 455 kHz output of the second mixer is fed through a ceramic filter CF1 to the
limiter and discriminator IC U3. CF1 provides additional adjacent channel selectivity
for 25 kHz versions and all of the adjacent channel selectivity for 12.5 kHz versions.
Page 10
RF Technology R350/R500
5.3
VCO Section
5 CIRCUIT DESCRIPTION
CF1 and its termination resistors R15 and R24 are the only component differences in
the two versions.
The limiter/discriminator IC U3 further amplifies the signal and passes it through CF2.
CF2 does not contribute to the adjacent channel rejection but is used to reduce the
wide band noise input to the limiter section of U3.
The limiter section of U3 drives the quadrature detector discriminator. C31 and IF
tuned circuit L10 comprise the discriminator phase shift network.
U3 also has a received signal strength indicator output (RSSI). The RSSI voltage
connects to the test socket for alignment use. The RSSI voltage is also used by the
microprocessor for the adaptive noise squelch, carrier squelch and low signal alarm
functions.
Dual op-amp U2 is used to amplify and buffer the discriminator audio and RSSI
outputs.
5.3
VCO Section
The Voltage Controlled Oscillator uses a junction FET Q6 which oscillates at the
required mixer injection frequency. Varactor diode D4 is used by the PLL circuit to
keep the oscillator on the desired frequency. Transistor Q7 is used as a filter to reduce
the noise on the oscillator supply voltage.
5.4
PLL Section
Temperature compensated crystal oscillator XO1 is the frequency reference source for
the PLL Synthesizer. The frequency stability of XO1 is better than 1 ppm.
The 12.8 MHz output of XO1 is amplified by Q8 to drive the reference input of the
PLL synthesizer IC U4. This IC is a single chip synthesizer which includes a 1.1 GHz
pre-scaler, programmable divider, reference divider and phase/frequency detector. The
frequency data is entered a serial data link from the microprocessor.
The phase detector output signals of U4 are used to control two switched current
sources. The output of the positive and negative sources' Q10 and Q16, produce the
tuning voltage which is smoothed by the loop filter components to bias the VCO
varactor diode D4.
RF Technology R350/R500
Page 11
5
CIRCUIT DESCRIPTION
5.5
5.5 Audio Signal Processing
Audio Signal Processing
A 4 kHz low pass filter (U27b) is used to remove high frequency noise from the
signal. A 300 Hz high pass filter (U26a,b) the n removes the sub-audible tones. A 240
Hz notch filter (U26c,d) is used to improve the rejection of tones above 200 Hz.
The audio can be set for either 750 uS de-emphasis or a flat response by JP2. JP2
selects the feedback network of amplifier U27c.
After de-emphasis and filtering, the audio signal is applied to the inputs of two analog
switches (U17a,b). These switches are controlled by the micro-controller and squelch
or mute the audio to the line and monitor output circuits. The monitor audio can be
unsquelched by S1 which keeps U17a switched on.
The audio from U17a is adjusted by the volume control before connecting to the
monitor output amplifier U5. U5 drives the internal speaker and can also supply 3-5
watts to an external loudspeaker.
The audio from U17b is adjusted by RV3 before connecting to the line output IC
(U22a,b). U22 is a dual amplifier connected in a bridge configuration to drive the
600Ω line output transformer T1.
5.6
Noise Filter, Amplifier and Detector
The unfiltered audio from the discriminator is fed to trimpot RV4 which is used to set
the noise squelch threshold. From RV4 the audio goes to the noise filter (U27a). This
is a 10 kHz high pass filter and is used to eliminate voice frequency components.
The noise signal is then amplified by U27d and fed to the noise detector. The noise
detector consists of D6, Q17 and U26c. D6 and Q17 are a charge pump detector and
pull the input to U26c low as the noise increases. U26c has positive feedback and acts
like a Schmidt trigger. The output of U26c goes high when noise is detected. It
connects to the micro-controller and to analog switch U17d. U17d varies the gain of
the noise amplifier to provide approximately 2dB hysteressis.
5.7
Sub-Tone Filter and CTCSS
The discriminator audio is fed through cascaded low pass filters U28a and U28b to
filter out the voice frequency components. The filtered sub-tone audio is supplied to
the CTCSS hybrid and the rear panel system connector. The filtered output can be
used for re-transmission of CTCSS or DCS.
The CTCSS decoder module is a micro-controller base hybrid module. Under control
of the main microprocessor U15 it can decode all 38 EIA tones and 12 additional
commonly used tones. The decode bandwidth is set to 1% but may be changed to 2%
by a jumper on the printed circuit board.
Page 12
RF Technology R350/R500
5.8 Microprocessor Controller
5.8
5 CIRCUIT DESCRIPTION
Microprocessor Controller
The microprocessor controller circuit uses an advanced eight bit processor and several
support chips. The processor U15 includes EE memory for channel frequencies, tones,
and other information. It also acts as an asynchronous serial port, a synchronous serial
port and an analogue to digital converter.
The program is stored in U12, a CMOS EPROM. U13 is an address latch for the low
order address bits. U11 is used to read the channel select lines onto the data bus. U7 is
an address decoder for U11 and U12. U14 is a supervisory chip which keeps the
processor reset unless the +5 Volt supply is within operating limits. U16 translates the
asynchronous serial port data to standard RS232 levels.
The analog to digital converter is used to measure the received signal strength, tuning
voltage, dc supply voltage and the carrier squelch setting.
5.9
Carrier Operated Switch
The carrier operated switch is an opto-coupled (ISO1) output. Internal jumpers (JP4,
JP7, JP8, JP9) can be connected to provide loop source, loop switch, free switch and
various other configurations.
The COS can be set to be active (switch closed) on carrier or active in the absence of
carrier.
The generic term ``Carrier Operated Switch'' may be misleading in this case. SINCE,
if a sub-audible tone has been programmed for the channel in use, the COS is
controlled by carrier and tone detection.
5.10
Voltage Regulator
The dc input voltage is regulated down to 9.4 Vdc by a discrete regulator circuit. The
series pass transistor Q20 is driven by error amplifiers Q21 and Q22. Q23 is used to
start up the regulator and once the circuit turns on, it plays no further part in the
operation.
This circuit is short circuit and overload protected. It provides much better line
isolation and lower dropout voltage than can be obtained with current integrated
circuit regulators.
6
Alignment Procedure
The following procedures may be used to align the receiver for optimum performance.
Normally only RF alignment will be required when changing frequencies. IF
alignment should only be necessary after repairs on that part of the circuit.
RF Technology R350/R500
Page 13
6
ALIGNMENT PROCEDURE
6.1 Standard Input Sig nal
TCXO calibration may be required periodically due to crystal aging. The aging should
be less than 1 ppm/year.
6.1
Standard Input Signal
RF Signal Generator, 50Ω output impedance, Frequency range 350-520MHz, FM
modulation at 1kHz, deviation 1.5kHz peak for 12.5KHz channel spacing, 3.0kHz
peak for 25kHz channel spacing.
6.2
RF Alignment
1.
Select center frequency channel. Measure dc Volts on test socket pin 9 to pin 1.
Adjust C61 to read 4.25 to 4.75V, with Alarm LED off.
2.
Set signal generator to the center frequency channel frequency and connect to J1.
Modulation should be off. Measure the dc voltage on the test socket pins 7 to 1.
Adjust the generator level to get a reading of 1 - 2Vdc.
3.
Set signal generator to the center frequency channel frequency and connect to J1.
Modulation should be off. Measure the dc voltage on the test socket pins 7 to 1.
Adjust FL1, FL2, and FL3 for maximum reading, reducing the generator output
to keep the voltage below 2Vdc.
6.3
IF Alignment
1.
Set signal generator to the center frequency channel frequency and connect to J1.
Modulation should be off. Measure the dc voltage on the test socket pins 7 to 1.
Adjust the generator level to get a reading of 1-2Vdc.
2.
Set signal generator to the center freque ncy channel frequency and connect to J1.
Modulation should be off. Measure the dc voltage on the test socket pins 7 to 1.
Adjust L5, L6, L7, L8 for maximum reading. Reduce generator output to keep
below 2 Vdc.
3.
Set generator level to 10µV. Measure the frequency at U3 pin 9, and adjust L9
to obtain a frequency of 455kHz ±10Hz.
4.
Set generator level to 1000µV (1mV), and switch the modulation on. Measure
the audio level at the test socket between pins 6 and 1. Adjust the line level
(RV3) to obtain approximately 1Vrms.
5.
Maintain generator level at 1000µV (1mV), modulation on. Measure the audio
level at the test socket between pins 6 and 1. Adjust L10 for maximum reading.
6.
Maintain generator level at 1000µV (1mV), modulation on. Measure the audio
level between pins 16 and 5 of P1. Adjust RV1 for 0.5Vrms.
Page 14
RF Technology R350/R500
6.4 Line Level Adjustment
7.
6.4
1.
6.5
6 ALIGNMENT PROCEDURE
Set generator level to 0.25µV, and measure SINAD on test socket pins 6 and 1.
Reduce generator level to obtain 12dB SINAD. Carefully adjust L5,L6,L7,L8 to
obtain the best SINAD. Reduce the generator output to maintain 12dB SINAD.
Line Level Adjustment
Set generator level at 1000µV (1mV), modulation on, tuned to the center
frequency channel frequency, apply signal to J1. Measure the audio level on pin
6 of the test socket wrt pin 1. Adjust RV3 for 350m Vrms.
TCXO Calibration
1.
No input is required. Measure the frequency at the junction of R69 and R26 (LO
input to mixer) on the top of the PCB. Adjust XO1 for an LO frequency within
100Hz of the required value. The required value is center frequency plus or
minus 45.000MHz, plus for carrier frequencies below 450MHz, minus
otherwise.
7
Specifications
7.1
General Description
The receiver is a high performance, frequency synthesized, narrow band FM unit
which can be used in conjunction with transmitter and power supply modules as a base
station or as a stand alone receiver. All necessary control and 600Ω line interface
circuitry is included.
7.1.1
Channel Capacity
Although most applications are single channel, it can be programmed for up to 100
channels numbered 0-99. This is to provide the capability of programming all channels
into all of the receivers used at a given site.
7.1.2
CTCSS
The CTCSS tone or no tone can also be programmed for each channel. So that each
channel number can represent unique RF and tone frequency combination.
RF Technology R350/R500
Page 15
7
SPECIFICATIONS
7.1.3
7.1 General Description
Channel Programming
The channeling information is stored in a non-volatile memory chip and can be
programmed via the front panel test connector using a PC and RF Technology
supplied TecHelp software.
7.1.4
Channel Selection
Channel selection is by eight channel select lines. These are available through the rear
panel connector.
A BCD active high code applied to the lines selects the required channel. This can be
supplied by pre-wiring the rack connector so that each rack position is dedicated to a
fixed channel.
BCD switches inside the receiver can be used to pre-set any desired channel. These
eliminate the need to externally select the channel.
7.1.5
Microprocessor
A microprocessor is used to control the synthesizer and squelch functions and
facilitate the channel frequency programming. With the standard software it also can
provide fault monitoring and reporting.
7.2
Physical Configuration
The receiver is designed to fit in a 19 inch rack mounted frame. The installed height is
4 RU (178 mm) and the depth 350 mm. The receiver is 63.5 mm or two Eclipse
modules wide.
7.3
Front Panel Controls, Indicators and Test Points
7.3.1
Controls
Mute defeat switch - toggle (Overrides CTCSS, noise and carrier squelch at the
monitor output)
Monitor Speaker Volume - Knob
Line Output Level - screwdriver adjust multi-turn pot
Noise Squelch Setting - screwdriver adjust multi-turn pot
Carrier Squelch Setting - screwdriver adjust multi-turn pot
Page 16
RF Technology R350/R500
7.2
7.3.2
7 SPECIFICATIONS
Physical Configuration
Indicators
Power ON - Green LED
Squelch Open - Yellow LED
Fault Indicator - Flashing Red LED
7.3.3
Test Points
Line Output Level –
Pin 6 + Gnd (pin 1).
Receive Signal Strength –
Pin 7 + Gnd (pin 1).
Tuning Voltage –
Pin 9 + Gnd (pin 1).
Serial Data (RS232) –
Pins 2/3 + Gnd (pin 1).
7.4
Electrical Specifications
7.4.1
Power Requirements
Operating Voltage - 10.5 to 16 Vdc
Current Drain - 450mA Max.
Polarity - Negative Ground
7.4.2
Frequency Range and Channel Spacing
Frequency
350-380 MHz
370-400 MHz
400-430 MHz
450-490 MHz
485-520 MHz
25 kHz
R350A
R350B
R500A
R500B
R500C
RF Technology R350/R500
12.5 kHz
R350AN
R350BN
R500AN
R500BN
R500CN
Page 17
7
SPECIFICATIONS
7.4.3
7.4 Electrical Specification
Frequency Synthesizer Step Size
12.5 kHz
7.4.4
Frequency Stability
±1 ppm over 0 to +60 C, Standard
7.4.5
Nominal Antenna Impedance
50Ω
7.4.6
IF Frequencies
First IF frequency 45 MHz
Second IF frequency 455 kHz
7.4.7
Sensitivity
0.25µV (-119dBm) for 12dB SINAD
0.28µV (-118dBm) for 20dB Quieting
7.4.8
Selectivity
25 kHz spacing - 80dB per RS204C
12 kHz spacing - 70dB per ECR-235
7.4.9
Spurious and Image Rejection
90dB
7.4.10
Intermodulation
80dB per RS204C
Page 18
RF Technology R350/R500
7 SPECIFICATIONS
7.4.11 Modulation Acceptance BW
7.4.11
Modulation Acceptance BW
25 kHz spacing - 7.5 kHz per RS204C
12.5 kHz spacing - 3.75 kHz per RS204C
7.4.12
Noise Squelch
Adjustment Range: 6 - 26dB SINAD Minimum
Attack Time:
Release Time:
threshold
20 ms above 20dB Quieting
150~ms at 20dB Quieting decreasing to 20ms above 2µV preset
Hysteresis: Hysteresis is equal to approximately 2dB change in noise quieting
7.4.13
Carrier Level Squelch
Carrier level squelch can be used when it is necessary to set the opening point above
26dB SINAD as may be required in link applications. The minimum adjustment range
is 1 to 200µV.
7.4.14
Receiver Frequency Spread for -1dB degradation
R350: ≈7 MHz (approximately 2%)
R500: ≈10 MHz (approximately 2%)
7.4.15
Receiver Conducted Spurious Emissions
Less than -57dBm from 1 to 2900 MHz
7.4.16
Audio Frequency Response
600Ω Line and Direct Output:
response or 750µs de-emphasis
+1/-3dB 300-3000 Hz relative to either a flat
Sub-Audio Output: +1/-3dB 67-250 Hz
7.4.17
Audio Output Level
600Ω Line: Adjustable -10 to +10dBm
RF Technology R350/R500
Page 19
7
SPECIFICATIONS
7.4.18 Audio Distortion
Monitor Loudspeaker: 3 Watts with external speaker, 0.3 Watt with internal
speaker
Discriminator and Sub-Audio: Nominally equal to 1 volt peak at rated system
deviation
7.4.18
Audio Distortion
750µs De-Emphasis: Less than 3% at 1 kHz and 60% of rated system deviation
Flat Response: Less than 10% at 1 kHz and 60% of rated system deviation
7.4.19
Channel Select Input / Output
Coding : 8 lines BCD coded 00-99
Logic Input Levels:
0 <= 1.0 Volts
1 >= 3.5 Volts
Internal 10K pull down resistors selects Channel 00 when all inputs are O/C.
7.4.20
Carrier Operated Switch Output
Floating Opto-Coupler Output: The carrier operated switch output is via an optocoupler.
Collector and emitter connections are available to allow connection for source or sink.
The opto-coupler can be linked inside the receiver to be on when a carrier is detected
or to be on in the absence of carrier.
Via 600Ω Line: Internal connections are provided so that the opto-coupler can be
connected to the 600Ω line for use over a single pair. This permits remote switching
with no extra connections.
Current Source/Sink, Collector Voltage: The COS output is implemented with an
opto-coupler whose ratings are:
Ic = 10mA Maximum
Vc = 30 Volts Maximum
7.4.21
CTCSS
The CTCSS decoding is provided by a hybrid module. This provides programmable
decoding of all 38 EIA and 12 other common tones. Refer to table 4.
Page 20
RF Technology R350/R500
7 SPECIFICATIONS
Frequency
No Tone
EIA Number
67.0
69.4
71.9
74.4
77.0
79.7
82.5
85.4
88.5
91.5
94.8
97.4
100.0
103.5
107.2
110.9
114.8
118.8
123.0
127.3
131.8
136.5
141.3
146.2
151.4
156.7
159.8
162.2
165.5
167.9
171.3
173.8
177.3
179.9
183.5
186.2
189.9
192.8
196.6
199.5
203.5
206.5
210.7
218.1
225.7
229.1
233.6
241.8
250.3
254.1
A1
B1
C1
A2
C2
B2
C3
A3
C4
B3
A4
B4
A5
B5
A6
B6
A7
B7
A8
B8
A9
B9
A10
B10
A11
B11
A12
B12
A13
B13
A14
B14
A15
B15
A16
B16
A17
Table 4: Tone Squelch Frequencies
RF Technology R350/R500
Page 21
A
ENGINEERING DIAGRAMS
7.4.22
7.5 Connectors
External Squelch Input
An external input is provided to squelch or mute the receiver audio output. This may
be used in conjunction with an external decoder or to mute the receiver during
transmissions.
External Squelch Input can be connected to the T/R Relay pin on Eclipse transmitters
to mute the receiver during transmission.
7.5 Connectors
7.5.1
Antenna Connector
Type N Female Mounted on the module rear panel
7.5.2
Power & I/O Connector
25-pin “D” Male Mounted on the rear panel
7.5.3
Test Connector
9-pin “D” Female mounted on the front panel
A Engineering Diagrams
A.1
Block Diagram
Figure 1 shows the block signal flow diagram.
A.2
Circuit Diagram
Figure 2 shows the detailed circuit diagram with component numbers and values.
A.3
Component Overlay Diagram
Figure 3 shows the PCB overlay guide with component positions.
Page 22
RF Technology R350/R500
A
B
C
D
Flo
Fx
1
Tx DATA
Rx DATA
+13.8
CARRIER SQ.
TUNE V.
RSSI
MA1
VCO
Q6,Q7
Q10-Q16
MA4
Q5
PLL IC
12.5/10 KHz
STEPS
U4
A/D
2
ASYNC.
DATA I/O
600 MHz
C45,C46,L13
4 RESONATOR
HELICAL FILTER
FL2, FL3
MICROPROCESSOR CONTROLER
U7,U11-U16
ALM
2
+15 dBm
LO OUTPUT
RF AMP.
Q1
250Hz
LOOP FILTER
VCO ISOLATION AMPS
MA3
MA2
LO AMPLIFIER
2 RESONATOR
HELICAL FILTER
FL1
BCD CHANNEL CODE
EXT. SQ. *
BNC
1
LOCK DETECT
DATA
12.8
MHz
MX1
Q2,Q3
1st IF AMP.
3
TONE DATA
TONE DETECT
NOISE DETECT
SQUELCH
1 PPM TCXO
XO1
Flo = Fx - 45
+13 dBm
DOUBLE BAL.
MIXER
3
U2A
* NOT ON PCB 30/9101
LPF
Q4
U2B
HPF
U26
300 Hz
RSSI
AUDIO AMP.
2nd IF AMP.
RSSI BUFFER
U27B
4 KHz
U3B
LIMITER
/DISCRIMINATOR
45 MHz
XTAL FILTER
XF1
4
4
ISO1
750 uSec
U27C
NOISE FILTER
U27A
10 KHz
LPF
U28A,B
250 Hz
U1
2nd MIXER
COS-
COS+
DE-EMPHASIS
45 MHz
XTAL FILTER
XF2
SQ.
SW SPST
U17B
NOISE AMP.
5
455 KHz AMP.
Q27*, U3A
Date:
File:
T1
U5
LINE OUT
LINE OUT
TRANSFORMER
6
Revision
Rev 1
6
7-Aug-1998
Sheet 1of 2
D:\RFT_MasterFiles\..\9131-RxUHF-block.sch
Drawn By: JBS after RHM
Number
11/9131/0001 UHF Rx
17/8 Leighton Place, Hornsby, Sydney, 2077 Australia
Orcad B
Size
Title R F Technology
-
+
NOISE DETECT
SUB-TONE OUT
TONE DETECT
TONE DATA
BPF
CF2
455 KHz
MONITOR AMP.
LINE AMP.
U22A,B
SW SPST
U17A
NOISE DETECTOR
D6,Q17,U17D,U26C
SW SPST
S1
CTCSS
DECODER
MODULE
H1
BPF
U27D
45.455 MHz
Y1
2nd OSC.
CF1
455 KHz
5
A
B
C
D
IN
OUT
+12 Vdc Direct Output
Free Switch Output
JP7, JP8, JP9 - Direct Output COS (JP4 2-3)
Source +l2Vdc Loop
Free Switch Output
JP7, JP8, JP9 - dc Loop COS Configuration (JP4 1-2)
Active on Signal
Active on No Signal
JP6 - COS Polarity
dc Loop Configured
by JP7, JP8, JP9
dc Loop Not Used
JP4 - 600 Ohm Line dc Loop COS
Hi-pass & Notch In
Flat Response
JP3 - Audio Filter in/Out
750 uSec. de-emphasis
Flat response
JP2 - Audio Response
Notch Filter
JP1 - 240 Hz Notch Filter
JP7
2-3
1-2
JP7
2-3
1-2
RECEIVER Jumper Options
JP8
OFF
OFF
JP8
ON
ON
Position
2-3 *
1-2
1-2 *
2-3
Position
Position
2-3 *
1-2
Position
1-2 *
2-3
Position
1-2 *
2-3
JP9
OFF
OFF
JP9
1-2 *
2-3
* = Standard Factory Configuration
No alarm output
Alarm LED signal output brought to DB25 pin 7
JP19 – LED Alarm output
Squelch operation normal
Squelch Defeat on active low input at DB25 pin 19
JP13 – Squelch Defeat
THE FOLLOWING JUMPERS ARE VALID ON
RX PCB VERSION 30/9131/0004 OR LATER
27C256
27C64
JP11 EPROM Type
Position
1-2 *
2-3
Position
1-2 *
2-3
Position
2-3 *
1-2