UNIDEN 2020
Sid 8 (26)
CAUTION
(
1
) During transmitter tuning, do not keep the final tube running untuned for a long period
of time. Make quick adjustment of PLATE and LOAD controls.
(
2
) High voltage is generated especially inside of the final amplifier and also bottom of the
PA compartment. Don’t touch part of them.
2.
PA IDLING CURRENT ADJUSTMENT
2-1.
Test Equipment Required
(
1
) None
2-2.
Adjustment Procedure.
(
1
) Set MODE SWITCH to USB.
(
2
) Set STANDBY SWITCH to MANU
(
3
) Adjust the BIAS potentiometer, R16 on the rear panel so as to indicate
GREEN TRIANGLE MARK on the meter.
3.
GENERATOR UNIT ALIGNMENT
3-1.
Test Equipment Required
(
1
) RF voltage Meter
(
2
) AF milli- volt Meter (mV)
(
3
) Audio Generator (AG)
(
4
) Frequency Counter.
(
5
) Oscilloscope
3-2.
Preparations
Take out Generator Unit (PC-080) and put a SERVICE EXTENSION BOARD
in its place, then connect the GENERATOR UNIT to the EXTENSION
BOARD.
3-3.
(
1
) Connect RF voltage meter the (RF VTVM) to Pin 16 of J18.
(
2
) Adjust L510 to get maximum meter readings.
(
3
) Remove RF VTVM and connect frequency counter to Pin 16 of J18.
(
4
) Set MODE SWITCH to USB, and adjust trimmer capacitor C541 so that the
frequency counter indicates 6,187.000 kHz.
(
5
) Set MODE SWITCH to TUNE, and adjust trimmer capacitor C542 so that
the counter reading indicates 6,187.750 kHz.
Summary of Contents for 2020
Page 21: ...UNIDEN 2020 Sid 24 26 PLL Unit PC 086 Operation Unit PC 085...
Page 22: ...UNIDEN 2020 Sid 21 26 1 E 1 F 1 G 1 H 1 H...
Page 23: ...UNIDEN 2020 Sid 22 26 5 uS DIV 0 1 uS DIV 0 1 mS DIV 5 uS DIV 0 1 mS DIV 1 I 1 I 1 J 1 J 1 K...
Page 25: ...UNIDEN 2020 Sid 25 26...
Page 26: ...UNIDEN 2020 Sid 26 26...