TUNER ALIGNMENT PROCEDURE
47
48
Note: Refer to Figure 1 while reading the below procedure.
C45 Tuner: FM ALIGNMENT PROCEDURE
1.
Connect an FM Signal Generator to Antenna Input.
2.
Connect Distortion Analyzer to the TUNER IN/OUT RCA
jacks.
3.
Remove Top Cover and AM/FM TUNER Cover. Turn On the
AC rocker switch. Press the red Standby button to turn the
unit On.
4.
Select Tuner with the Zone A selector knob. Put Tuner into
FM mode and tune to 87.5MHz.
5.
Adjust L5 (FM OSC Coil) for 3.5VDC at R46.
6.
Tune to 108.5MHz and adjust C59 (FM OSC Trimmer
Capacitor) for 24.5VDC at R46.
7.
Repeat steps 4, 5 and 6 as necessary for a tuning range of
3.5VDC to 24.5VDC at R46.
8.
Tune the Generator and Tuner to 90MHz and adjust Coils:
L2 (FM MIX), L3 (FM RF) and L4 (FM ANT) for best sensi-
tivity.
9.
Tune the Generator and Tuner to 104MHz and adjust
Trimmer Capacitors: C60 (FM MIX), C62 (FM RF) and C63
(FM ANT) for best sensitivity.
10.
Repeat 8 and 9 until no improvement in sensitivity is noted.
11.
Tune Tuner to 90MHz with no RF Input and adjust T9 (FM
DETector Primary) for zero volts between TP1 and TP2
relative (connector J6).
12.
Tune the Generator to 90MHz and adjust the RF Output to
1000uV and 100% MONO modulation at 1000Hz. Then
adjust T8 (FM DETector SECondary) for lowest distortion.
13.
Reduce the Generator Output to minimum and detune the
Generator so the Receiver picks up only noise, then
recheck the voltage between TP1 and TP2 (connector J6).
Adjust T8 and C65 if needed.
If it is not 0+/- 0.2VDC, repeat steps 11 and 12. If there is
interference from a station on this frequency, tune the Tuner
to a nearby frequency free from interference for this mea-
surement.
14.
Tune the Generator to 90MHz with a 1000uV output. Then
switch the Generator to stereo (left only) and adjust T10
(FM IF Transformer) for the lowest distortion at the TUNER
IN/OUT RCA jacks.
15.
Switch the Analyzer to the right channel TUNER IN/OUT
jack and adjust R71 (MPX SEParation Pot) for best separa-
tion (minimum output).
16.
Switch the Generator to the Right Channel and the Ana-
lyzer to the Left Channel. Adjust R71 (MPX SEParation
Pot) and check for best separation (minimum output).
17.
Disconnect voltmeter from TP1 and TP2 (J6). Reduce the
generator output to 5uV and adjust R73 (STEREO SWITCH
Pot) so the MPX light (Dot next to Signal Strength number)
just comes on.
C45 Tuner: AM ALIGNMENT PROCEDURE
1.
Connect an AM Signal Generator to the RAA1 ”EXT ANT”
pin of the 5 pin connector. Connect a Distortion Analyzer to
the C45 rear panel TUNER IN/OUT RCA jacks.
2.
Tune to bottom of band, and adjust T11 (AM OSC Coil) for
3.0VDC at R46.
3.
Tune to top of band and adjust C64 (AM OSC Trimmer
Capacitor) for 26.0VDC at Connector R46.
4.
Repeat steps 4 and 5 as necessary for a Tuning Voltage
Range of 3.0 to 26.0VDC.
5.
Tune the Generator and Tuner to 600kHz, then adjust Coils:
T101 (AM ANT) and T12 (AM RF) for best sensitivity.
Note: Coil T101 (AM ANT) is located on the RAA1. It is
labeled “L1”.
6.
Tune the Generator and Tuner to 1400kHz, then adjust
Trimmer Capacitors: C106 (AM ANT) and C61 (AM RF) for
best sensitivity. Note: Trimmer Capacitor C106 (AM AMT) is
located on the RAA1. It is labeled “C1”.
7.
Repeat 8 and 9 until no improvement in sensitivity is noted.
8.
Note the initial position of R70, and then adjust R70 fully
counter clockwise. Tune the Generator and Tuner to
1400kHz (20uV, 30% modulation), then Adjust T7 (AM IF)
for maximum signal.
9.
Tune the Generator and Tuner to 1400kHz (100mV, 30%
modulation). Slowly adjust R70 clockwise until the C45
front panel signal strength display reads “9”.
10.
Check both channels for signal to noise performance, and
re-adjust R70 and as needed.
Figure 1
C45
Содержание C45
Страница 4: ...4 REAR VIEW TOPVIEWWITHCOVERREMOVED SECTION LOCATION ...
Страница 5: ...5 6 BLOCK DIAGRAM C45 ...
Страница 6: ...7 8 BLOCK DIAGRAM con t ...
Страница 7: ...INTERCONNECT 1 9 10 C45 ...
Страница 8: ...NOTES 11 12 ...
Страница 9: ...13 15 14 C45 MAIN 749850 SH 1 OF 5 2A ...
Страница 10: ...16 18 17 MAIN 749850 SH 2 OF 5 2B ...
Страница 11: ...MAIN 749850 SH 3 OF 5 2C 19 20 C45 ...
Страница 12: ...MAIN 749850 SH 4 OF 5 2D 21 22 ...
Страница 14: ...25 26 MAIN 749850 PCB 2 ...
Страница 15: ...DISPLAY 749851 SH 1 OF 2 3A 27 28 C45 ...
Страница 17: ...DISPLAY 749851 PCB 3 31 32 C45 ...
Страница 19: ...6 CHANNEL 749852 PCB 4 35 36 C45 ...
Страница 21: ...DATA 749854 SCH and PCB 6 39 40 C45 ...
Страница 23: ...TUNER 049084 SCH 8 43 44 C45 ...
Страница 24: ...45 46 TUNER 049084 PCB 8 RAA1 SECTION 9 Rev B ...
Страница 26: ...49 50 NOTES ...
Страница 37: ...EXPLODED VIEW 61 62 C45 ...
Страница 38: ...63 64 EXPLODED VIEW con t ...
Страница 40: ...NOTES 66 ...
Страница 41: ...REPACKING INSTRUCTION C45 67 ...