Sharp 14VT10X1, Service Manual

Page: 39 / 138

Checking of recording level
Measuring
instrument
VTVM
Mode
Self-recording/playback
Input signal 1
Test point Audio output terminal
Control
Specification - 8
1. Feed 1 -8 signal to the audio input
terminal. Make self-recording and playback of
the signal.
2. Make sure the output at the audio output
terminal is 8 3
3. If out of readjust the playback level and the
bias current.
ADJUSTMENT OF THE IF CIRCUIT
Adjustment of the RF AGC
Measuring
Oscilloscope
instrument
Signal generator
Mode EE
Input signal Colour bar signal
Test point IF
Pin of IF Pack (Video Output)
Adjusting point control)
1 . R e c e i v e t h e bar signal (input field
strength: 80
2. Observe the video output terminal waveform on
the oscilloscope. Adjust control) in
the IF pack until the noise disappears from the
oscilloscope screen and the waveform nearly
comes into sync.
before
Adjustment of the AFT
Input signal
frequency uniwave
Colour bar signal (70
Test point
IF
Pin of IF Pack (Video Output)
Adjusting point
TOO2 (AFT coil)
Specification
1.
2.
3.
4.
R e c e i v e t h e bar signal (input field
strength: 70
U s i n g t h e s i g n a l g e n e r a t o r , f e e d t h e
frequency signal to the
tuner IF output terminal.
Set the tuning switch to the VHF or UHF position.
Keep the tuning button or depressed
until the beating on the oscilloscope screen be
m i n i m u m . .
Set the tuning switch on the normal position.
Adjust TOO2 (AFT coil) so that beating on the
oscilloscope screen be minimum.
RF AGC
AFT
IF Pack
Figure 2-15.
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