21
HCD-RG55/RG55S
TUNER SECTION
AM IF Adjustment
SECTION 5
ELECTRICAL ADJUSTMENTS
Procedure:
1. Set the frequency of the AM RF signal generator to 1000 kHz
(at 10 kHz step) or 999 kHz (at 9 kHz step).
2. Tune the set to AM 1000 kHz (at 10 kHz step) or 999 kHz (at 9
kHz step).
3. Adjust IFT101 so that the reading on level meter becomes in
maximum.
FM Tuned Level Adjustment
Procedure:
1. Supply a 98 MHz signal at 28 dB from the ANTENNA
terminal.
2. Tune the set to 98 MHz.
3. Adjust RV101 to the point (moment) when the TUNED
indicator will change from going off to going on.
Adjustment Location: MAIN board
set
FM RF Signalgenerator
FM ANTENNA terminal
(JK101)
75
Ω
coaxial
Carrier frequency : 98MHz
Modulation : AUDIO 1kHz,75kHz
deviation (100%)
Output level : 28dB (at 75
Ω
open)
set
FM RF Signalgenerator
FM ANTENNA terminal
(JK101)
75
Ω
coaxial
Carrier frequency : 98MHz
Modulation : AUDIO 1kHz,75kHz
deviation (100%)
Output level : 60dB (at 75
Ω
open)
MAIN BOARD Component side
RV101: FM TUNED LEVEL
T101:NULL
IFT101:AM IF
Null Adjustment
Procedure:
1. Supply a 98 MHz signal at 60 dB from the ANTENNA
terminal.
2. Tune the set to 98 MHz.
3. Measure voltage between pin 21 and pin 23 of IC 101. Adjust
T101 ubtil the voltage becomes 0 V.
Adjustment Location: MAIN board
Adjustment Location:
set
AM RF Signalgenerator
AM ANTENNA terminal
(JK101)
75
Ω
coaxial
30% amplitude
Modulation by
400Hz signal
Output level : as low as possible
set
16
Ω
PHONES jack(JK801)
level meter
