Sony BM-21 Service Manual page 35

Tape Speed 2.4cm/s Adjustment
Switch position
TAPE SPEED Switch : 2.4 cm
Procedure:
test
WS-48A
(3 kHz, 0 dB)
set
1. Play back WS-48A (tape center portion) in FWD mode.
Adjust the RV602 so that the frequency counter reads 1,490±
15 Hz.
2. Play back WS-48A (tape center portion) in REV mode.
Confirm that the reading of frequency counter is within 2.5 %
from the reading in step 1.
Adjustment Parts Location Diagram :
frequency
counter
18 Ω
J102
EAR
AUDIO BOARD (SIDE B)
RV601
(TAPE SPEED 4.8cm ADJ.)
RV602
(TAPE SPEED 2.4cm ADJ.)
BM-21/23
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