Technics RS-676US

iV. MEASUREMENT & ADJUSTMENT METHOD
NOTE:
1. Make sure heads are clean.
2. Make sure capstan and pressure roller are clean.
3. Judgeable room temperature: 20+5°C (68+9°F)
4.
Source Selector:
ITEM
LINE IN 8. Dolby FM Switch: OUT
MEASUREMENT & ADJUSTMENT
5. Output Level Control: MAX.
6. Tape Select Switch: NORMAL
7. Dolby NR/MPX Filter Switch: OUT
REMARKS
Pressure of Pressure Roller
Equipment:
* Cassette Type Tension
Gauge (max. 500 gr)
\
Q
1. Place UNIT into playback mode.
2. Hook tension gauge to pressure roller shaft top (A), and
pull gauge in direction opposite to pressure of pressure
roller against capstan (See fig. 10).
3. Read pressure indicated on gauge immediately when pres-
sure roller moves away from capstan and stops rotating.
Standard Value: 400+50 gr
Adjustment method
Adjust by bending the (B) part of the pressure roller spring
(See fig. 10).
* Playback Mode
Takeup Tension
Equipment:
* Cassette Torque Meter
(RP-8063N)
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+15 gr-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. 11).
Plate Spring
Fig. 11
Head Azimuth Adjustment
Equipments:
* VTVM
* Oscilloscope -
* Test Tape (Azimuth)
.C-AA
«x Tape Path Viewer
. RT-8133
Record/playback head adjustment
1. Test equipments connection is shown below.
LINE OUT
(av)
(Test Tape) (Playback Mode)
Fig. 12
2. Play azimuth tape (C-AA 6.3 kHz).
3. Adjust record/playback head angle adjustment screw (C).
in fig. 13 so that output level at LINE OUT becomes maxi-
mum. ;
4. Measure both channels, and the level difference between
channels shoud be minimised by adjusting.
5. After adjustment lock head adjustment screw with lacquer.
(Oscilloscope)
Erase head adjustment
1. Test equipments connection is the same above but use the
tape path viewer (RT-8133) in stead of test tape (C-AA).
2. Play this tape.
3. Adjust screw (D) shown in fig. 14 so that the tape may
not get curled or malformed by tape guide of the erase
head.
4. After adjustment lock head adjust screw with lacquer.
* Playback Mode
Fig. 13
Erase Head