Technics RS-646DS-D User Manual

iV. MEASUREMENT & ADJUSTMENT METHOD
NOTE:
1.
. Make sure capstan and pressure roller are clean.
2
3. Judgeable room temperature: 20-+5°C (68+9°F)
4
Make sure heads are clean.
. Bias selector: Low
Pressure of pressure roller
Equipment:
* Tension gauge (max. 500 gr)
5. Dolby NR switch: OUT
7. Output level control: MAX
MEASUREMENT & ADJUSTMENT
Place UNIT into playback mode.
2. Hook the tension gauge to pressure roller lever and pull it in the direc-
tion of the arrow as shown in fig. 9.
. Measure the tension at the moment when the pressure roller moves
away from the capstan.
Standard value: 390+60 gr |
l
Adjustment method
Bend the part (A) of the pressure roller spring in either direction shown
by the arrow until the correct pressure is attained.
6. Equalizer selector: 120.8
REMARKS
* Playback mode
Pressure ~
roller spring
Fig. 9
Takeup tension
Equipment:
* Cassette torque meter
(SRK-CT or RP8063)
1. Mount cassette torque meter on UNIT.
2. Place UNIT into playback mode and read takeup torque.
3. Measure several times and determine the mean value.
Standard value: 55+15gr-cm |
If the measured value is not within standard, firstly clean the rotational
parts of the mechanism with alcohol, and if it still is not within standard,
make the following adjustment.
Adjustment method
Adjust by turning the plate spring attached in the takeup reel table (See
fig. 10).
* Playback mode
Plate spring
Fig. 10
Head azimuth adjustment
Equipment:
* VTVM
* Oscilloscope
* Test tape (azimuth) --- C-AA
Record/playback head adjustment
1. Test equipment connection is shown below.
VTVM
Fig. 11
Test tape Playback mode Oscilloscope
. Play azimuth tape (C-AA, 6.3 kHz).
. Adjust record/playback head angle adjustment screw (8) in fig. 12 so
that output level at LINE OUT becomes maximum.
. Measure both channels, and adjust levels for equal output.
. After adjustment lock head adjustment screw with lacquer.
* Playback mode
R/P Head

Technics RS-646DS-D Specifications

General

Brand	Technics
Model	RS-646DS-D
Category	Cassette Player
Language	English