Technics RS-676US - Page 15

ITEM
MEASUREMENT & ADJUSTMENT
REMARKS
Overall Gain
Equipments:
* AF Oscillator
* VTVM
* ATT
* Oscilloscope
* Test Tape (Reference
Blank Tape)...C-RA
1. Test equipments connection is shown in fig. 23.
R/P Head
Oscilloscope)
(Test Tape) (Playback Mode) (VTVM)
Fig. 23
. Place UNIT into record mode.
. Supply 1kHz signal (—24dB) from AF oscillator, through
ATT, to LINE IN.
. Adjust ATT until monitor level at LINE OUT becomes 0.42V
(—7 dB).
. Make recording.
. Playback recorded tape, and make sure the value at LINE
OUT on VTVM becomes 0.42 V.
. lf measured value is not 0.42V, adjust VR9 (L-CH), VR10
(R-CH) (See fig. 30 on page 19).
8. Repeat fromstep (2).
How To Check Recording Current
LINE IN
R/P Head
Fig. 24
. Test equipments connection is shown in fig. 24.
. Stop bias oscillation by unsoldering a wire (C) shown in
adjustment parts location on page 19.
. Supply 1kHz signal (—24dB) again and adjust ATT until
monitor level at LINE OUT becomes 0.42 V.
. Measure voltage and then calculate recording current by
formura given below.
Value read on VTVM (V)
Recording current= 10 (0)
| Standard Value: 40”A |
. At this time, set the tape selector switch to CrOz position
and confirm variation of recording current.
| Standard Value: 602A-+1dB |
«x Record/Playback Mode
* Record Level Control
MAX.
* Standard Input Level:
+3 dB
—244+3 dB
—36+43dB
—20+3dB
R25, R26 are shown in
AMP circuit board on page
24.
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