GE MLSH041, Руководство по обслуживанию

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ALIGNMENT AND TROUBLESHOOTING PROCEDURES
LBI-38438A 13
STEP
METERING
POINT
TUNING
CONTROL
METER
READING PROCEDURE
1 TP201
Control
Voltage
Monitor
L206 7.0 VDC Select highest frequency transmit
channel. With 50 ohm load on the
antenna connector J1, key the radio.
Monitor TP201 with digital voltmeter
and tune L206 for 7.0 VDC ±0.1 V.
Unkey the radio.
2 TP201 CV201 7.0 VDC Select the highest frequency receive
channel. Monitor TP201 with digital
voltmeter and tune CV201 for 7.0
VDC ±0.1 V.
3 TP201 3.5-7.5
VDC
Select lowest frequency channel.
Voltage should be between 3.5 – 7.5
VDC transmit and receive for lowest
and highest frequency channels.
4 J201 +1 to +8
dBm
RX/EX injection level should be
b1 and +8 dBm.
5.1.3 Transmitter Frequency Adjustment
STEP
METERING
POINT
TUNING
CONTROL
METER
READING PROCEDURE
NOTE
This step assumes the frequency is
measured when the transmitter is first
keyed. If delayed, the rapidly rising
ambient temperature must be taken
into consideration. The oscillator
frequency should be set at 25°C
ambient temperature.
1 J201 (or J1) FREQ
TRIM
Control on
TCXO
(XU201)
Channel
Operating
Frequency
Press the PTT switch while monitoring
RX/EX injection frequency at J201.
Adjust FREQ TRIM Control on TCXO
(XU201) for the assigned channel
frequency ±0.5 PPM.
5.1.4 Receiver Frequency Adjustment
No receiver frequency adjustment is required.
With proper alignment of EX injection frequency, RX injection frequency will
automatically be correct.
5.1.5 Modulation Level Adjustment
Procedure for synthesizer Transmit Deviation
1. Select the highest frequency channel.
2. Rotate CG DEV ADJUST, RV202 fully counterclockwise.