Sony WM-DDIII - Tape Speed Adjustment; Playback Head Azimuth Adjustment; Playback Level Adjustment; Phase Check

WM
2-2. ELECTRICAL ADJUSTMENTS
Tape Speed Adjustment
Setting:
VOLUME control: mechanical mid
TAPE SELECT switch: NORM
DOLBY NR switch: OFF
Procedure:
Mode: playback
test tape
WS-48A
(3 kHz, OdB)
digital frequency
counter
\J HEADPHONES
1. Open the solder bridge shown below.
2. Turn RV601 so that frequency reading be¬
comes in 3090 Hz ± 10 Hz. (at the ending part
of the test tape)
3. Resolder the adjustment patterns opened in
step 2 above. Now frequency reading should be¬
comes in 3000 Hz ± 9 Hz.
Specification:
Digital frequency counter
3000 Hz ± 9 Hz
Adjustment Location:
— main board —
Adjustment
patterns
I O 1 ^ tc>rO
X60I M
mm lu
UL—C-— i—
7 1 T
Playback Head Azimuth Adjustment
Setting:
VOLUME control: mechanical mid
TAPE SELECT switch: NORM
DOLBY NR switch: OFF
Procedure:
1. M o d e : playback
test tape
P-4-A WO u
UD/
32n
LJ
L_ I 1—
set 1 i % |
— —K _Lj-i
-
U HEADPHONES
2. T urn the adjustment screw for the maximum
output levels. If these levels do not match, turn
the adjustment screw until both of output
levels match together within 1 dB.
Screw
position
3. P hase Check
Mode: playback
test tape
P-4-A063
(6.3kHz, —WdB)
L-CH R‘CH
peak peak
32SI oscilloscope
HEADPHONES
Screen pattern
0 @ ®
in phase 45° 90° 13 5° 18(f
good
wrong
8