Technics RS-615US-D - Page 9

Head azimuth adjustment
Equipment:
+ VTVM
* Oscilloscope
+ Test tape (azimuth) --- C-AA
MEASUREMENT & ADJUSTMENT
Record/playback head adjustment
1. Test equipment connection is shown below.
LINE OUT
6
VTVM Oscilloscope
Fig. 12
Test tape Playback mode
. Play azimuth tape (C-AA 6.3kHz).
. Adjust record/playback head angle adjustment screw (B) in fig. 13 so
that output level at LINE OUT becomes maximum.
. Measure both channels, and adjust levels for equal output.
. After adjustment lock head adjustment screw with lacquer.
REMARKS
+ Playback mode
R/P Head
Tape speed
Equipment:
* Digital electronic counter or
frequency counter
(RP8067)
* Test tape --» C-WAT
Tape speed accuracy
1. Test equipment connection is shown below.
LINE OUT
Playback mode Digital electric counter
Test tape
Fig. 14
. Play test tape (C-WAT 3,000Hz), and supply playback signal to fre-
quency counter.
. Measure this frequency.
. On the basis of 3,000Hz, determine value by following formula:
f — 3,000
3,000
where, f = measured value
. Take measurement at middle section of tape.
Tape speed accuracy = X 100 (%)
Standard value: 1.5%
Adjustment method
1. Play the test tape (middle).
2. Adjust the tape speed adjustment VR shown on page 14 so that tre-
quency becomes 3,000 Hz.
Tape speed fluctuation
Make measurements in same manner as above (beginning, middle and end
of tape), and determine difference between maximum and minimum values
and calculate as follows:
fi — fe
Tape speed fluctuation = 3.000
x 100 (%)
f1 = maximum value
f2= minimum value
ns 7
| Standard value: 1% |
* Playback mode
Screw driver