Technics RS-M04 Service Manual

ITEM MEASUREMENT & ADJUSTMENT
® Playback frequency 1. Test equipment connection is shown
response in fig. 32. Playback frequency response chart
Condition:
2.
Place
UNIT
into
playback
mode.
one
ahh
*
Playback
mode
3.
Playback
the
frequency
response
test
63Hz
auty
8kH2
¥
* Normal tape mode tape (QZZCFM). +4503 TEM o0H7 soon: 1KHZ
* Output level control --- MAX | 4. Measure output level at 315 Hz,
if
en
12.5kHz,
SkHz,
4kHz,
1kHz,
250Hz,
9
ai
ra
*
Oscill
125Hz
and
63Hz
and
compare
each
a
—
—2dB
Test tae QZ7CEM. output level with the standard frequency mire Pe ee
*
ee
Zz
Z
Zz
315Hz, at LINE OUT. aes oe 4A ie
5. Make measurement for both channels. Iki
SkHz
6. Make sure that the measured value is
within the range specified in the frequency
response chart.
Fig. 35
fay
@ Playback gain Test equipment connection is shown in fig. 32.
Condition: 2. Playback standard recording level portion on test tape (QZZCFM 315Hz), and using VTVM measure
* Playback mode the output level at LINE OUT jack.
* Normal tape mode 3. Make measurement for both channels.
* Output level control --- MAX
Equipment: Standard value: around 0.7V
+*VTVM — * Oscilloscope ;
* Test tape --- QZZCFM Adjustment
1. If measured value is not standard, adjust VR1 (L-CH), VR2 (R-CH) (See fig. 23).
2. After adjustment, check “Playback frequency response” again.
@ Bias leak
Test equipment connection is shown in fig. 36.
Condition:
Place
UNIT
into
record
mode.
* Record mode Adjust trap coil L5 (L-CH), L6 (R-CH) so that measured
* Metal tape mode value on VTVM becomes minimum.
4. Take adjustment for both channels.
TP7 (L-CH) L5 (L-CH)
TP8 (R-CH)
WrNr
Equipment:
*VTVM__ * Oscilloscope
Oscilloscope
VIVM
@ Erase current . Test equipment connection is shown in fig. 37.
Condition: 2. Place UNIT into record mode and measure voltage at test
* Record mode point 9. head
« Metal tape mode 3. Determine erase current with the following formula:
: ; Voltage across both ends of R206
Equipment: Erase current (A) 1 (@) oO tp OL
x VTVM — * Oscilloscope VTVM_ Oscilloscope
Standard value: 95+5mA (Tape selector --- Metal) Fig. 37
_ If measured value is not within standard, adjust VR203.

Technics RS-M04 Specifications

General

Brand	Technics
Model	RS-M04
Category	Cassette Player
Language	English