-37-
ELECTRICAL ADJUSTMENT -3/5
<FM Adjustment>
Make the following preparation for FM adjustment.
Preparation
• Measuring instruments: Standard Signal Generator (S.S.G) /Oscilloscope/Millivoltmeter
1) Connect the unit and measuring instruments as shown in the diagram below.
2) Position the loop antenna connected to S.S.G. and the one connected to the unit 60cm apart.
CH2
CH1
CH2
CH1
Standerd Signal Genertaor
SET
FM ANT
HP OUT(L)
HP OUT(R)
AC MILLIVOLTMETER
OSCILLOSCOPE
OUTPUT
5. FM Tracking Adjustment
Requirement:
• Test point: HP OUT
• Adjustment location: L002
1) Set S.S.G. to FM, carrier 87.5MHz with 75KHz modulation, source at 1KHz.
2) Tune the unit to the receiving frequency at FM 87.5KHz.
3) While monitoring the waveform at 1KHz through the oscilloscope, lower the output level of S.S.G. maximum
(till a certain degree or noise is monitored).
4) Adjust L002 so that the millivoltmeter indicates maximum.
