Rotel RT-226 Technisches Handbuch Seite 7

FM SIGNAL
GENERATOR
300 OHM
DUMMY
FM IF and RF Alignment Procedure
Instruments: FM Signal Generator, H.D. Analyzer and
Oscilloscope.
Set Function Selector to FM position.
• Connect FM Signal Generator
minal.
• Connect Oscilloscope and H.D. Analyzer to "OUT-
PUT" jack.
A. FM IF Alignment
1. Set Signal Generator frequency at 98MHz (400Hz
100% Mod.) and adjust the Tuning to Max. output.
(The antenna terminal voltage should be 1mV,
60dB).
2. Tuning Signal Meter to obtain Max.
3. Adjust IF coil L 108 and L109 set distortion
minimum lower then
B. FM RF Alignment
1. Set Signal Generator frequency at 106MHz (400Hz
100%Mod.) and also tune receiver at 106MHz on
the dial scale. Then adjust FM OSC trimmer CT 3
(on Front-end) to obtain maximum deflection on
OSCILLOSCOPE
H -D. ANALYZER
REAR PANEL
O
to FM antenna ter-
0.3%
CHASSIS TOP VIEW (FM PORTION )
L108 L107
FM OSC FM IFT
ICIOI
IC301
L 204
C
Fig. 3. FM IF and RF Alignment
Abb. 3. UKW-ZF.und
Fig. 3. Alignement
Scope.
2. Set the receiver at 90MHz on the dial scale, and
change the frequency of Signal Generator so that
the output
Then make sure Signal Generator frequency stays
within 90MHz±
3. Sensitivity
106MHz
maximum
balance sensitivity
4. Adjust FM OSC coil L 104 and FM RF coil L 101,
L102, L103 and L 109 as discribed below only
when tracking and sensitivity
to
a. Fine tune
90MHz,
and L 104.
b. Fine tune
106MHz, and adjust CT 1, CT2 and CT3 so that
maximum
c. Repeat step a and b to obtain enough effect.
L106
FM t IFT
L201
L109S
L 202
L104 OSC
L203
CT3 C 2
Hook-Up
HF-Abgleich
FM IF et HF
of the OUTPUT becomes
150KHz.
on this alignment must be attempted at
by adjusing CTI and CT 2 to obtain
deflection on Scope and fine tune to
at 90 and 106MHz.
adjustments are not
Signal Generator
and adjust L106, L 101 L102, L 103
Signal Generator
output is obtained.
L 101
FM ANT
L 102
CTI
maximum.
and receiver to
and receiver to