Disc TN310-5 VHF AM Synth Tx.qxd

DANIELS
TECHNICAL NOTES
TM
ELECTRONICS LTD.
MT-3 Radio Systems
The VT-3A130-S transmitter is a synthesized multichannel AM transmitter capable of operating in 25
/ 8.333 KHz channels. The VT-3A130-S transmitter operates in the 118 to 138 MHz aviation band.
A modular design allows each of the transmitter’s modules, MT-3 Transmitter Main Board, MT-3
Audio Processor, VT-3A130 Amplifier, and OST-3A130 Synthesizer, to be individually assembled
and tested. This facilitates construction, tuning and maintenance as well as troubleshooting procedures. The synthesizer module can be programmed to have up to 16 channels in the 118 to 138 MHz
frequency band. Channel 16 can be programmed from the front panel frequency select handle.
TRANSMITTER
MADE IN CANADA
MADE IN CANADA
VT-3A130-SYD410
TX
NORM
OFF
KEY TX
MIC
RF OUT
REFERENCE
INPUT
Daniels Electronics Ltd
1 2 8.0 0 0 0
*
Specifications
Frequency Band
Channel Spacing
Transmitter Switching Range
RF Output Power
Duty Cycle
Emission of Radio Frequency Energy
Carrier Noise Level
Frequency Stability
Modulation Type
Audio Frequency Distortion (@ 25 °C)
Audio Frequency Distortion (-40 °C to +40 °C)
Audio Frequency Response
Output Impedance
Operating Temperature
Standby Current
Transmit Current (3.0 W)
118 - 138 MHz
8.333 KHz and 25 KHz
Unlimited
1.0 to 3.0 Watts adjustable (carrier only)
100% (-30 °C to +60 °C)
-60 dBc
< -45 dB
± 1.0 ppm (-30 °C to +60 °C) (-40 °C to +60 °C optional)
6K00A3 (AM)
< 5% THD @ 85% modulation (1 KHz Tone, 50 KHz LPF)
< 10% THD @ 85% modulation (1 KHz Tone, 50 KHz LPF)
Flat audio; +1/-5 dB (350 Hz - 2.5 KHz)
50 Ω (Type N Connector)
-30 °C to +60 °C (-40 °C to +60 °C optional)
< 30 mA
< 2.50 A
Specifications tested using RTCA DO-186A, TIA/EIA-603 and ETSI Section 8.8 EN300 676
Models Available
VT-3A130-SYD410
Enhanced Synthesized, AM, 3.0 W, 118 - 138 MHz, with FP frequency select handle
Transmitter Operating Frequency
The transmitter is initially aligned at the factory for the center of the 118 to 138 MHz frequency range. No re-alignment of
the transmitter is required to change frequencies. The transmitter operating frequency can be set as follows:
- Channel 1 is programmed by the four BCD switches located on the Transmitter Main Board.
- Channels 2 through 15 are programmed in the synthesizers internal memory (done at the factory, or by a synthesizer channel programmer)
- Channel 16 is programmed by the front panel frequency select handle (exclusive to the AM product)
Control of the channel selection for a transmitter module can be made through four channel select jumpers mounted on the
motherboard. Optionally, control of the channel selection can be made through the control modules optional rotary switches
or the auxiliary control connector (for external control of channel selection).
43 Erie Street
Victoria, B.C.
Canada V8V 1P8
TN310 Rev 5-0-0 Aug 06
Toll Free
Phone:
Fax:
Canada & U.S.A.
1-800-664-4066
1-877-750-0004
International
Phone: 250-382-8268
Fax: 250-382-6139
© Copyright 2006 Daniels Electronics Ltd. All rights reserved.
e-mail:
web:
Internet
sales@danelec.com
www.danelec.com
Page 1 of 2
T h i s p r o d u c t h a s b e e n d i s c o n t i n u e d a n d i s n o l o n g e r m a n u f a c t u r e d b y D a n i e l s E l e c t r o n i c s L td .
TN310 VT-3A130-SYD VHF AM Synthesized Transmitter
DANIELS
TECHNICAL NOTES
TM
ELECTRONICS LTD.
MT-3 Radio Systems
Transmitter Alignment Procedures
Synthesizer Alignment:
No synthesizer alignment is required. The synthesizer is
aligned at the factory for use over the entire frequency
range.
B
A
Audio Processor Alignment:
No audio processor alignment is required. The audio
processor is aligned at the factory for use over the entire
frequency range.
B
B
A
B
A
A
Remove the four front panel screws (A) and four side panel screws (B)
to slide the transmitter outer cover off and expose the Main Board,
Local Oscillator, Audio Processor Board and Amplifier.
Amplifier Output Power Adjustment:
The power amplifier carrier output level can be adjusted
from 1.0 to 3.0 Watts. Key the transmitter with no modulation and adjust R19 (RF Level) to achieve the desired RF
output power between 1.0 and 3.0 Watts. Apply a 1.0 KHz
tone at -8 dBm to the transmitter balanced input and adjust
R35 (Modulation Adjust) to obtain 85% of AM modulation.
Frequency Select Handle Operation:
The frequency select handle is used to designate the operating frequency for channel 16 of the AM RF module. To operate
the frequency select handle, set the AM module on channel 16 (using the motherboard jumpers, external control or rotary
switch option) and ensure jumper JU73 on the Motherboard is installed.
1) The display is normally in a low power sleep mode. To display the current frequency press either the L (decrease frequency) or the K (increase frequency) buttons. This will display the current channel number (for 2 seconds), then the current
frequency (for 3 seconds). The display will then go back to sleep.
2) Press the * (center) button to display the current lock status (“Locked” or “Unlocked”). To lock the buttons, press the K
button, and to unlock the buttons, press the L button.
3) To change the current operating frequency, ensure the lock status is “unlocked” , then press either L or K to wake up the
display, then use the L or K buttons to change the frequency. The L or K buttons have two modes of operation. Single press
the buttons for single channel steps (8.333 KHz). Hold the button in for 6 seconds and the frequency will change by 66.66
KHz per step, and after 9 seconds of the button being pressed the frequency will change by 166.66 KHz per step. The operating frequency is set to the displayed value once the L or K buttons are released.
Note: For complete alignment procedures, refer to the instruction manual. These notes are for reference only.
43 Erie Street
Victoria, B.C.
Canada V8V 1P8
Page 2 of 2
Toll Free
Phone:
Fax:
Canada & U.S.A.
1-800-664-4066
1-877-750-0004
International
Phone: 250-382-8268
Fax: 250-382-6139
© Copyright 2006 Daniels Electronics Ltd. All rights reserved.
e-mail:
web:
Internet
sales@danelec.com
www.danelec.com
TN310 Rev 5-0-0 Aug 06
T h i s p r o d u c t h a s b e e n d i s c o n t i n u e d a n d i s n o l o n g e r m a n u f a c t u r e d b y D a n i e l s E l e c t r o n i c s L td .
TN310 VT-3A130-SYD VHF AM Synthesized Transmitter
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