SONY HCDGRX20
Service Manual

SECTION 4 MECHANICAL ADJUSTMENTS
Precaution 1. Clean the following parts with a denatured alcohol-moistened swab: record/playback head pinch rollers erase head rubber belts capstan idlers 2. Demagnetize the record/playback head with a head demagnetizer. 3. Do not use a magnetized screwdriver for the adjustments. 4. After the adjustments, apply suitable locking compound to the parts adjusted. 5. The adjustments should be performed with the rated power supply voltage unless otherwise noted. Torque Measurement Torque FWD FWD back tension FF/REW Torque meter CQ-102C CQ-102C CQ-201B Meter reading 40 to 70 g � cm (0.56 - 0.97 oz � inch) 1 to 5 g � cm (0.01 - 0.07 oz � inch) 55 to 140 g � cm (0.76 - 1.94 oz � inch)

SECTION 5 ELECTRICAL ADJUSTMENTS
DECK SECTION
1. 2. 3. 4. 5.

0 dB=0.775V

6.

Demagnetize the record/playback head with a head demagnetizer. Do not use a magnetized screwdriver for the adjustments. After the adjustments, apply suitable locking compound to the parts adjusted. The adjustments should be performed with the rated power supply voltage unless otherwise noted. The adjustments should be performed in the order given in this service manual. (As a general rule, playback circuit adjustment should be completed before performing recording circuit adjustment.) The adjustments should be performed for both L-CH and RCH. Tape P-4-A100 WS-48B Signal 10 kHz, �10 dB 3 kHz, 0 dB Used for Azimuth Adjustment Tape Speed Adjustment

Record/Playback Head Azimuth Adjustment (Deck A, Deck B) Note: Perform this adjustments for both decks. Procedure: 1. Mode : Playback
test tape P-4-A100 (10kHz, �10dB) SPEAKER terminal (JK401) set

level meter

2.

Turn the adjustment screw and check output peaks. If the peaks do not match for L-CH and R-CH, turn the adjustment screw so that outputs match within 2 dB of peak.

L-CH peak

output level within 2dB

within 2dB

screw position

R-CH peak L-CH peak R-CH peak screw position

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