TC-PX100 - Sony Audio Service Manual (repair manual). Page 14

— 30 —

L-CH peak

L-CH peak

R-CH peak

R-CH peak

screw position

output
level

within 
1dB

within 1dB

angle of
adjustment
screw

4. Enter the FWD mode and perform steps 1 to 3.
5. Check that the phase difference between L-CH and R-CH is in

the range of in-phase to 90

°

.

6. After adjustment, lock the screw with locking compound.

Procedure :
Mode : FWD playback

1. Enter the FWD playback mode, and play back test tape.
2. Adjust the adjustment control (variable resistor) of the motor

(M902) until the frequency counter reading becomes 3,000 Hz
± 90 Hz.

3. Confirm that the tape speed deviation between tape top and tape

end is within 3%.

test tape 

P-4-A100

(10kHz, –10dB)

set

LINE OUT

47k 

Ω

level meter

Note:

•

Perform this adjustment after the head is turned around.
(If the head is positioned in the FWD direction, turn around
the head and start adjustment from the REV mode as
described below.)

* When the azimuth adjustment is performed, the azimuth

adjustment screw must end up with rotation of tightening
direction (i.e. clockwise direction).

Adjustment procedure :
1. Mode: REV playback

2. Turn the azimuth adjustment screw for the maximum output

level of L-CH and R-CH.
If the peak levels do not match for L-CH and R-CH, turn the
adjustment screw until both of output levels match together
within 1 dB of peak.

3. Phase Check

Mode: REV playback

test tape 

P-4-A100

(10kHz, –10dB)

L-CH

R-CH

set

47k 

Ω

47k 

Ω

oscilloscope

LINE OUT

V

H

Oscilloscope Lissajous waveform

in phase

45 

°

90 

°

180 

°

135 

°

Good

Wrong

Adjustment screw (FWD side)

Adjustment screw (REV side)

test tape 

WS-48B (3kHz, 0dB)

set

L- or R-CH of LINE OUT 

47k 

Ω

frequency counter

M902

adjustment control
(variable resistor)

W. RMS (JIS) within 0.3%
(test tape: WS-48B)