Technics RS-676US

17
ITEM
MEASUREMENT & ADJUSTMENT
REMARKS
Overall Frequency Response
(AS a Standard for
Adjustment)
1.
When the frequency response between the middle- and
high-frequency range becomes higher than the standard
value, as shown by the solid line in the above diagram,
increase the bias current (by turning VC301 or VC302
clockwise).
. When it becomes lower, as shown by dotted line, reduce
the bias current (by turning VC301 or VC 302 counter-
clockwise).
Note:
ais
For adjustment when the bias current is lower than the
standard value 0.12mA, use the procedure indicated in
adjustment 2, because reducing the bias current beyond
this point may worsen the distortion factor.
. For the method of bias current measurement. refer to
“Bias Current Adjustment” on page 12.
Adjustment 2—Using the peaking coil for recording equaliza-
tio n
4 kHz 6 kHz 8kHz 12 kHz
fe
Fig. 29
. When the frequency response is flat in the middle-fre-
quency range and makes a sharp rise in the high-fre-
quency range, as shown by the solid line above, reduce
the inductance of the peaking coil (L3 or L4: for record-
ing equalization), thereby reducing the amount of record-
ing equalization (by turning L3 or L4 in the direction
opposite to that of the adjustment arrow marked on the
Unit).
. When it shows a sharp drop in only the high-frequency
Ad
range, as shown by the dotted line, increase the induct-
ance of the peaking coil, thereby increasing the amount
of recording equalization (by turning L3 or L4 in the same
direction as the adjustment arrow attatched on the Unit).
justment of the overall frequency response by using CrO2
tape.
NO
1
2.
3.
4.
5.
Ad
1.
TE:
. Dolby NR/MPX Filter switch is set to both OUT position.
Tape selector switch is set to CrOz position.
Overall frequency response for CrOz must measured after
confirmation of overall gain using normal tape.
Never adjust the bias current.
Must use technics CrOz tape.
justment method
In case the overall! frequency response in the high-fre-
quency rangé 10~14kHz is higher than the standard
value, increase the resistance of VR11 or VR12 (record-
ing equalization curve controls for CrOz frequency re-
sponse), which is done by turning in the direction opposite
to that indicated on the adjustment label attatched on the
Unit.
. Overall frequency response in the high-frequency range,
10~14 kHz, is lower than the standard value, decrease the
resistance of VR11 or VR12, which is done by turning in
the same direction as indicated on the adjustment label.