Technics RS-M228X - Page 5

RS-M228X
ITEM MEASUREMENT & ADJUSTMENT
5. Make measurement for both channels.
6. Make sure that the measured value is within the range specified in the frequency response chart
(fig. 9).
Playback frequency response adjustment
1. Open or short the circuit's connection points to adjust playback frequency response (see fig. 10).
2. The frequency response when connection points (a) (L-CH) and (a’) (R-CH) are shorted/open
changes as short/open condition at connection points changes as described below (table 1).
Short/open conditions, in turn, differ with sets due to the differences in fine adjustments made prior to
shipping. If readjustments are required, set conditions so that results are as close to the standard
value as possible.
Connection point
(a) (L-CH), (a') (R-CH)
6 kHz 8kHz 10 kHz 12.5kHz
around around around around
Short
+0.2dB}
+04dB)
+08dB)
+12dB
around around around around
ope -~0.2dB] -04dB| —08dB) —1.2dB
Table 1
Connection.“
point (a') /
C7
%390P_ Connection
Record/ point (a)
Playback Head
Connection
point (a)
L-GH)
@ Playback gain _ Test equipment connection is shown in fig. 3.
Condition: . Playback standard recording level portion on test tape (QZZCFM 315 Hz, OdB), and using VTVM
measure the output level at LINE OUT jack.
* Playback mode
Ge, . Make measurement for both channels
* Normal tape mode
Equipment: Standard value: 0.4V+1¢dB
SVM. «« Oselloseope (around 0.42V: at test points TP3 (L-CH) and TP4(R-CH
*
Test
tape
---
QZZCFM
a
:
P
3
ane
a(R
E
i
Adjustment
1. If measured value is not within standard, adjust VR1 (L-CH), VR2 (R-CH) (shown in fig. 1)
2. After adjustment. check “Playback frequency response” again