Page 6 - Combined_OCR

RF Alignment - TM-L1 Line Voltage 117 Volts A.C.
Voltage Chart
1. Adjust the cores of the following coils as indicated: Reading in Volts
A. The core of L4 should be level with the top of Base Emitter
the coil form. Ref. No. Collector
o &
B. L3 should have no core in it. h c o o ° 6.5 4.0 3.3
2. Set the RF signal generator as follows : NJ cn O 8 6.9 3.0 2.5
A. RF to the receiving frequency. ’ X D 6.9 1.9 1.4
B. No modulation. Q\> 7.6 1.9 1.2
3. Connect an AC voltmeter to the speaker terminals : cc O O v] 8.5 2.3 2.2
A. Set the meter to the 1 volt scale. 4.2 2.3 1.7
4. Adjusting C7 and C11. rO O /O O C 4.4 2.2 1.6
A. With no RF signal, adjust the volume control 4.4 2.4 1.7
of the receiver until the noise reaches 1 volt. 9.2 2.7 2.2
B. Increase the RF signal generator output until Q12 9.2 4.3 3.8
Q14 4.9 1.0 0.9
the AC voltmeter decreases to 0.5 volt.
C. Adjust C7 and Cll until the voltmeter reading Q15 Unsquelched 9.2 0.0 0.3
drops to approximately 0.1 volt; then, de­ Squelched 0.2 0.0 0.1
crease the RF input to the receiver until the Q16 9.0 2.8 2.1
voltmeter reads 0.5 volt again. Repeat the Q17 0.0 9.0 9.2
process with C7 and Cll until no more quiet­ Q18 0.0 9.0 9.2
ing is achieved. The RF section is now tuned 019 16.5 9.6 9.2
to the most sensitive point.
NOTE : There is no crystal frequency adjustment neces -
sary. Each crystal is tested at the factory for accuracy
and activity; therefore, they should be on frequency
when you install them.

RF Alignment - TM-L2
1. Adjust the cores of the following coils as indicated:
A. The core of L4 should be level with the top of
the coil form.
B. L3 should have no core in it.
2. Set the RF signal generator as follows :
A. RF to the receiving frequency of channel 1. o o
B. No modulation. o 0
3. Connect an AC voltmeter to the speaker terminals :
A. Set the meter to the 1 volt scale. s o
4. Adjusting Cl, C2, C3, C4, C5, C6 and Cll.
A. With no RF signal, adjust the volume control oO
of the receiver until the noise reaches 1 volt.
B. Turn the selector switch counter-clockwise un­ H
til a stop is reached. This is channel 1.
C. Increase the RF signal generator output until
the AC voltmeter decreases to 0.5 volt.
D. Adjust Cl until the voltmeter reading drops to
approximately 0.1 volt;then, decrease the RF
input to the receiver until the voltmeter reads
0.5 volt again. Repeat this process with Cl \ \ '-CI/CI9
until no more quieting is achieved. The RF \ C2/C20
section for channel 1 quieting is now tuned to '-C3/C2I
the most sensitive point. C4/C22
E . Adjust C 2 thru C 6 by repeating the above
steps with the selector switch advanced to the
next position.
5. Choose the channel which comes nearest to the cen­
ter frequency of the group of frequencies that you
have ordered and set the selector switches on that CRYSTAL SWITCH AND
channel. Repeat steps 4A thru 4D adjusting Cll TRIMMER MTG. BRKT.
for maximum quieting. Cll is on the large print­ (Front View)
ed circuit board.
NOTE : There is no crystal frequency adjustment nec­
essary. Each crystal is tested at the factory for ac­
curacy and activity; therefore, they should be on fre­
quency when you install them.

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