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ALIGNMENT INSTRUCTIONS
PRE-ALIGNMENT INSTRUCTIONS
Allow a 20 minute warm-up period for the receiver and test equipment.
VIDEO IF ALIGNMENT
Connect the synchronized sweep voltage from the sweep generator to the horizontal input of the oscilloscope for horizontal deflection.
The sweep generator output lead should be terminated with its characteristic impedance, usually 50 ohms.
DUMMY
ANTENNA
470mmf
Direct
SWEEP
GENERATOR
COUPLING
High side to point ^> .
Low side to chassis.
High side to ungrounded
tube shield floating over
mixer-oscillator tube
(V202). Low side to
chassis.
SWEEP
GENERATOR
FREQUENCY
44MC
(10MC Swp)
MARKER
GENERATOR
FREQUENCY
39. 75MC
41.25MC
45. 75MC
39.75MC
41. 25MC
47. 25MC
41.25MC
42. 75MC
45.0MC
45.75MC
CHANNEL
Between
any two
channels
CONNECT
SCOPE
Vert. Amp. thru
10K to point <g> .
Low side to chassis,
(across video det.
load).
ADJUST
Al, A2
A3, A4,
A5, A6
A7, A8,
A9 and
Mixer
Plate
Coil
REMARKS
Set sweep generator output to produce 3 volts
peak to peak on scope. Adjust Al and A2
alternately for maximum gain and symmetry
with the 45. 75MC positioned as shown in
Fig. 1 . The 39. 75MC marker can fall
within ± . SMC of the specified frequency.
if the desired response cannot be obtained,
check to see that the cores are entering
their respective windings from opposite
ends of the coils.
Connect a clip lead from point <£> to
chassis. Connect a clip lead from point <§>
to point <E> . Use high scope gain and
adjust A3 thru A6 for MINIMUM marker
amplitudes as in Fig. 2. A3 controls
39. 75MC marker, A4 controls 41. 25MC
marker and A5 and A6 controls 47. 25MC
marker.
Disconnect clip lead from point <£) and
connect to chassis.
Adjust for maximum
gain and symmetry of response similar to
Fig. 3 with markers as shown. A7 affects
low side of curve and A8 affects high side.
SOUND IF ALIGNMENT
Connect an adjustable attenuator between the antenna and the receiver terminals. Tune in a modulated TV signal and adjust the attenuator
until the signal is below the limiting level of the 6BN6 (V6) as evidenced by a hiss similar to super-regeneration in the sound. Adjust A10,
All, A12 and A13 for maximum sound and best quality. Adjust the buzz control (Rll) for MINIMUM buzz. If the hiss disappears during sound
alignment, further reduce the signal until the hiss returns.
F IG.I
FIG. 2
FIG. 3
MIXER
PLATE
COIL
Nl
*S*
PAGE 4
RF TUNER-TOP VIEW
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