Kenwood KVT-910DVD Service Manual page 48

KVT-910DVD/920DVD/930DVD/
940DVD/960DVD
X86 Circuit Adjustment Specification (K, R, H type)
Item
1. Adjusting image
detection coil
L103
2. Adjusting audio
detection coil
L101
3. Adjusting S-METER
VR102
4. Adjusting RF AGC
VR101
5. Diversity free-run
frequency
VR1
50
ADJUSTMENT
Adjustment Method & Value
1. Turn VR101 [RF-AGC] counter-clockwise as much as
possible.
2. Impresss sDC2.0V to TP [IF AGC] (IC101 #36).
3. Input fo=45.75MHz Mod=1KHz AM60% Level=100dBµ to
TP [IF] (CF1 #1).
4. Observe the waveform of TP [VIDEO] (IC101 #8) using an
oscilloscope, and adjust L103 so that the output level is at the
maximum.
1. Turn VR101 [RF-AGC] counter-clockwise as much as
possible.
2. Input fo=41.25MHz non-modulated Level=94dBµ to TP [IF]
(CF1 #1).
3. Connect a voltmeter to TP [SIF] (both ends of R107) and
adjust L101 to 0V ± 0.01V.
1. Turn VR101 [RF-AGC] to clock-wide direction as much as
possible.
2. Input RF signal 30dBµ 11CH color bar to ANT input
terminal.
3. Audio (P/S-6dB) non-modulated.
4. Connect a voltmeter to TP [IC101 #12] and adjustVR102
[SMET] to 3.5V ± 0.05V.
5. Set RF signal 70dBµ and adjust VR101 [RF-AGC] so that
the value of the voltmeter connected to TP [IC101 #12] is
4.6V ± 0.05V.
1. Connect frequency counter to PIN1 of CN5 [IC2 #7].
2. Connect Pin3 [IC2 #8] of CN5 and Pin2 [GND].
3. Adjust VR1 [15KHz] and set to 15734Hz ± 100Hz.
• ANT no signal
• If the waveform is
clipped, raise the DC
voltage somewhat.
• AC range
Maximu
• ANT no signal
• SlideVR101 so that
AGC will not be
effective at 30dBµ.
• Be sure to conduct
adjustment on the S-
METER before
adjusting RFAGC.
• ANT no signal
Condition