Adjustment Procedures; Tuner - Grundig RR 440 CD Serviceanleitung

Abgleichvorschriften / Adjustment Procedures

Adjustment Procedures

1. Tuner

Measuring instruments: Signal generator, Sweep generator, Oscilloscope, AF voltmeter
Adjustment
1. AM IF Couple in a sweep signal of 455kHz to ferrite aerial via a
loop aerial.
Oscilloscope to testpoint
Band switch: MW
2. MW Oscillator Var. capacitor to limit stop: MW f
Couple in a standard signal to ferrite aerial via a loop
aerial, (f
the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: MW
3. MW Aerial MW 558kHz, MW 1440kHz
bandpass Couple in a standard signal to ferrite aerial via a loop
aerial, (f
the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: MW
4. LW Oscillator Var. capacitor to limit stop: f
Couple in a standard signal to ferrite aerial via a loop
aerial, (f
the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: LW
5. LW Aerial LW 153kHz, LW 261kHz
bandpass Couple in a standard signal to ferrite aerial via a loop
aerial, (f
the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: LW
6. FM Oscillator Var. capacitor to limit stop: FM f
Couple in a standard signal via a 10nF capacitor to
testpoint
as low as possible so that the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: FM
7. FM Aerial FM 88MHz, FM 106MHz
bandpass Couple in a standard signal via a 10nF capacitor to
testpoint
as low as possible so that the signal is just visible).
Connect the AF voltmeter to the headphone socket.
Band switch: FM
2 - 2
Preparations
/
TP 5 TP 4
=515kHz, f
u
= 1kHz, m = 30%, U as low as possible so that
a
mod
= 1kHz, m = 30%, U as low as possible so that
a
mod
=292kHz
o
= 1kHz, m = 30%, U as low as possible so that
a
mod
= 1kHz, m = 30%, U as low as possible so that
mod a
=87.35MHz, f
u
= 1kHz, ∆f = 22.5kHz, U
/ (GND) (f
TP 2
TP 1
mod
= 1kHz, ∆f = 22.5kHz, U
/ (GND) (f
TP 1 TP 2
mod
Adjust to maximum with T501.
(GND).
=1630kHz At f (515kHz) adjust to maximum with T502.
o u
At f (1630kHz) adjust to maximum with VC501(C).
o
Repeat this adjustment alternately.
At 558kHz adjust to maximum with L504 (MW aerial coil,
move).
At 1440kHz adjust to maximum with VC501(D).
Repeat this adjustment alternately.
At f (292kHz) adjust to maximum with TC502.
o
At 153kHz adjust to maximum with L505 (LW aerial coil,
move).
At 261kHz adjust to maximum with TC501.
Repeat this adjustment alternately.
=108.25MHz At f (87.35MHz) adjust to maximum with L502 (bend).
o u
At f (108.25MHz) adjust to maximum with VC501(A).
o
Repeat this adjustment alternately.
a
At 88MHz adjust to maximum with L503 (bend).
At 106MHz adjust to maximum with VC501(B).
Repeat this adjustment alternately.
a
RR 440 CD
Adjustment Process
GRUNDIG Service