TM-471A
24
ADJUSTMENT
PCB Section
1. Setting
1) Power supply voltage
DC Power supply terminal : 13.8V
2. VCO lock
1) CH : TX high
Digital voltmeter
CV
TC402
5.5V
±
0.2V
voltage*
2) CH : RX high
TC401
5.5V
±
0.2V
3) CH : TX low
Check
0.5V or more
4) CH : RX low
3. IF coil
1) CH : RX center (Wide)
SSG
AFV
L301
3.25~3.35V (DC)
2) SSG output : –53dBm (501
µ
V)
Digital voltmeter
Mod : 1kHz
Dev : 3kHz
* Adjustment of TX VCO lock voltage
1. Remove R525, F501, R536 and R822 (all on component side).
2. Remove PCB from chassis.
3. Transmit and check voltage at [CV] point.
Warning :
Do not transmit if step “1.” is not complete.
4. Adjust of voltage can be done by tuning TC402.
Item
Condition
Test equipment
Terminal
Parts
Method
Specifications/
Remarks
Measurement
Adjustment
Transmitter Section
1. Frequency 1) CH : TX center
Frequency counter
ANT
Encoder
Adjust to center frequency
Within
±
20Hz
2) Transmit
knob
2. Maximum 1) CH : TX high
Power meter
VR601
43W
±
1W
power
2) Adjustment HEX value : FF
alignment 3) Transmit
3. High
1) CH : TX low
Encoder
40W
±
1.0W
power
CH : TX low’
knob
CH : TX center
CH : TX high’
CH : TX high
2) Transmit
4. Low
1) CH : TX low
25W
±
1.0W
power
CH : TX low’
CH : TX center
CH : TX high’
CH : TX high
2) Transmit
5. DCS
1) CH : TX low (Wide)
Modulation analyzer
Adjust the waveform as below
balance
CH : TC center (Wide/Narrow)
or Linear detector
CH : TX high (Wide)
(LPF : 3kHz)
2) Transmit
Oscilloscope
Item
Condition
Test equipment
Terminal
Parts
Method
Specifications/
Remarks
Measurement
Adjustment
