Grundig Sonoclock 30 SC 3340 LW, Service Document

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Sonoclock 30 SC 3340 LW
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Signal Source
1. AM signal generator (AM SG)
2. FM signal generator (FM SG)
3. Sweep generator (10.7 Mhz for FM)
Output Indicator
1. SSVM
2. Oscilloscope
3. Frequency Counter
General preparation
1. Check source voltage.
2. Set function switch to band being aligned
3. Turn volume control to minimum (unless noted otherwise)
4. Connect low side of signal and output indicator to chassis ground unless otherwise specified.
Keep ground connection close to high side connection.
5. Keep signal inout as low as possible to avoid AGC and AFC action
(set output indicator to high sensitivity.)
6. Standard modulation is 1000 Hz AT 30% amplitude for AM (1000 Hz at 22.5 kHz deviation for FM)
AM IF ALIGNMENT
Step
Signal source (AM RF Gen) Connect
to
Set signal to
Aligment indicator connect to
Oscilloscope or SSVM
Set radio dial to Adjust Adjust for Remarks
1 A standard radiation loop 455 KHz TP3 Detector Output Terminal Quiet point T2 Maximum
Volume control min
position
2 Repeat for maximum output
AM RF ALIGNMENT
Signal source (AM Signal Gen.)
connect to
Set signal to Alignment indicator Connect to Set radio dial to Adjust Adjust for Remarks
1
515 KHz
(modulated)
515 KHz
(lowest end)
T1 (Osc,
coil)
2
1745 KHz
(modulated)
1745 KHz
(Highest end)
C3 (Osc,
trim)
3
600 KHz
(modulated)
600 KHz L4 (ant coil)
4
1440 KHz
(modulated)
1400 KHz C4 (ant trim)
5 Repeat Steps 3 and 4 as necessary to minimize tracking error. Also repeat steps 1 and 2 if necessary.
FM ALIGNMENT PROCEDURE
Step
Signal source (FM RF Gen.)
Connect to
Set signal to
Alignment Indicator connect to
Oscilloscope or SSVM
Set Radio dial
to
Adjust Adjust for Remarks
1 T2 Maximum Symmetrical response
2 T4 (det. Coil)
Symmetrical response centered
10.7Mhz
3 Repeat Step 1 and 2 as necessary to obtain S curve linearity , with maximum output
FM RF ALIGNMENT
Step
Signal source (FM Signal Gen.)
Connect to
Set signal to
Alignment indicator (oscilloscope ,
VTVM Connect to
Set radio dial to Adjust Adjust for Remarks
1
87 MHz
modulated
*87MHz (lowest
end)
L1 (Osc, coil)
2
109 MHz
modulated
109MHz
(Highest end)
C2 (Osc,
trimmer)
3
90 MHz
modulated
90MHz
L2 (RF coil)
stretch or
squeeze
4
106 MHz
modulated
106MHz C1 (RF trim)
5 repeat steps 3 and 4 as necessary to minimum tracking error. Also repeat steps 1 and 2 if necessary.
* UK models must not be able to tune below 87.5 MHz.
BATTERY SENTINEL LEN ADJUSTMENT SETTING OF the 27 pin of IC2 (FOR SWITCH -ON POINT)
1. Plug unit into an AC outlet.
2. Set clock as described in owner's manual
3. Connect a DC power supply to the battery snap (inside battery compartment - no battery connected.)
Connect to DC voltmeter across battery snap.
4. Set DC power suply to 8.2 volts. Adjust 27 pin of IC2 to the point where the Battery Sentinel just turns on. Disconnect DC power supply and voltmeter.
5. Connect to a new battery . (Battery Sentinel Indicator will automatically be reset.)
A standard radiation loop antenna Across speaker voice coil Maximum
Volume control max-
position
Volume control min-
position
TP 1, GND (Test point) through
matching network if necessary
Across speaker voice coil Maximum
Volume control Max-
position
TP2 and GND
Sweep
centered 10.7
MHz
TP4 Detector Output Terminal Quiet point