Panasonic RS-612US-D - Measurement and Adjustment Methods; Mechanical Adjustments; Head Alignment and Tape Speed

IV. MEASUREMENT & ADJUSTMENT METHOD
NOTE:
1. Make sure heads are clean. 4. Dolby NR switch: OUT
2. Make sure capstan and pressure roller are clean. 5. Bias selector: LOW
3. Judgeable room temperature: 20+5°C (68 +9) 6. Equalizer selector: 120 uS
ITEM MEASUREMENT & ADJUSTMENT REMARKS |
Pressure of pressure roller | 1. Place UNIT into playback mode. + Playback mode
Equipment:
2.
Hook
the
tension
gauge
to
pressure
roller
lever
and
pull
it
in
the
direc-
tion
of
the
arrow
as
shown
in
fig.
6.
. Measure the tension at the moment when the pressure roller moves
away from the capstan.
* Tension gauge (max. 500 gr)
Standard Value: 400+50 gr
Adjustment
method
roller
‘|
J
EO
Bend
the
part
(A)
of
the
pressure
roller
spring
in
either
direction
shown
OX(A)
en
by
the
arrow
until
the
correct
pressure
is
attained.
spring
Fig. 6
Takeup tension 1. Mount cassette torque meter on UNIT. * Playback mode
Equipment: 2. Place UNIT into playback mode and read takeup torque.
* Cassette torque meter 3. Measure several times and determine the mean value.
(SRK-CT or RP8063)
Standard Value: 55+15gr-cm
Head azimuth adjustment Record/playback head adjustment * Playback mode
Equipment: 1. Test equipment connection is shown below.
* VTVM
* Oscilloscope LINE OUT
* Test tape (azimuth)---C-AA
R/P head
Test tape
Playback mode VTVM Oscilloscope
Fig. 7
. Play azimuth tape (C-AA 6.3 kHz).
3. Adjust record/playback head angle adjustment screw (B) in fig. 8 so Fig. 8
that output level at LINE OUT becomes maximum.
4, Measure both channels, and adjust levels for equal output.
. After adjustment lock head adjustment screw with lacquer.