Technics RS-M5 - Page 7

ITEM MEASUREMENT & ADJUSTMENT
Adjustment method
1. Playback the test tape (middle).
2. Adjust so that frequency becomes 3,000 Hz.
3. Tape speed adjustment VR shown in “Caution” on page 4.
Tape speed fluctuation
Make measurements in Same manner as above (beginning, middle and end of tape), and determine the
difference between maximum and minimum values and calculate as follows:
f1—f2 é
3.000 <x 100 (%)
f1 = maximum value, f2 = minimum value
Standard value: Less than 1%
1. Test equipment connection is as same a Playback frequency response chart
as “Head azimuth adjustment” (See 8kHz
Tape speed fluctuation =
@ Playback frequency
response
Condition:
fig.
9).
.
sie
+548
*
Playback
mode
2.
Place
UNIT
into
playback
mode.
+40B
pe
Oe
*
Tape
selector
3.
Playback
frequency
response
test
tape.
+24B
j____—"—~-
-
--
nae
.--
Normal
position
|
4:
Measure
output
level
at
8kHz,
4
kHz,
0dB
Oi
ie ta
Seca
hale
tie
noie
Oe
eu
Hn
cai
1kHz,
315Hz,
250Hz,
125Hz
and
=
_~-J-1.5¢B
quipment:
S
=
-{—2dB
63 Hz, and compare each output level
with standard frequency 315 Hz, at
LINE OUT.
5. Make measurement for both channels.
. Make sure that the measured value is within the range specified in the playback frequency response chart.
«VTVM * Oscilloscope 63Hz 125Hz 200Hz — 500Hz
* Test tape --- QZZCFM
Fig. 13
® Playback gain
Condition:
* Playback mode
* Tape selector
--» Normal position
. Test equipment connection is shown in fig. 9.
2. Playback standard recording level portion on test tape (QZZCFM 315Hz), and using VT VM measure
the output level at LINE OUT.
3. Make measurement for both channels.
Standard value: around 0.39V
Adjustment
1. If measured value is not within standard, adjust VR3 (L-CH), VR4 (R-CH) (See fig. 8).
2. After adjustment, check “Playback frequency response” again. |
Equipment:
* VTVM * Oscilloscope
* Test tape --- QZZCFM
@ Bias leakage
Condition:
* Record mode
* Input level control --- MAX
* Tape selector
-+» Metal position
. Test equipment connection is shown in fig. 14. Rucbrd rade
2. Place UNIT into record mode.
3. Adjust trap coils L5 (L-CH), L6 (R-CH), so that measured
value becomes minimum. R113(L-CH)
4 Make adjustment for both channels. phen
Record/playback
head
L5(L-CH)
L6(R-CH)
Equipment:
* VTVM « Oscilloscope
@® Erase current
Condition:
* Record mode
* Tape selector
--» Metal position
. Test equipment connection is shown in fig. 15. Récoed ‘iiode
2. Place UNIT into record mode and measure voltage at test aed "a frase
point 6.
3. Determine erase current with the following formula:
Voltage across both ends of R304 ieee pg wee
a
(>)
ane
VTVM
Oscilloscope
Fig. 15
Standard value: around 155mA (Tape selector --- Metal)
_ If measured value is not within standard, adjust as follows.
Erase current (A) =
Equipment:
*VTVM * Oscilloscope