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TV ALIGNMENT INSTRUCTIONS CCONTJ
HF TUNER ALIGNMENT
Remove the dummy converter tube and replace tae original 6J6 in its socket.
Disconnect the co-ax link from terminal 2 of the tuner termina board and connect a 39ft carbon resistor across terminals 1 and 2
Loosely couple the Irnk to terminal 2 of the terminal board.
Connect the negative lead of the 3 vo t battery to terminal 3 of the terminal strip, connect the positive lead to chassis.
The sweep generator output lead should be terminated iwith its characterist c impedance, usually 50 ohms.
Set the ine tuning control to the mid-position of its range.
DUMMY
ANTENNA
Two 120S2
carbon
res.
SWEEP
GENERATOR
COUPIING
Across antenna termin-
als with 120R in each
lead.
SWEEP
GENERATOR
FREQUENCY
Not used
I83MC
(10MC SWP)
Not used
85MC
(10MC SWP)
MARKER
GENERATOR
FREQUENCY
215. 75MC
181.25MC
185.75MC
87. 75MC
83.25MC
87. 75MC
Connect VTVM to Point D and adjust A24 for -3 vo t reading.
6. Repeat these retouching adjustments until proper response
Two 120ft
carbon
res.
Across antenna termin-
als with 120ft in each
lead.
Not used
183MC
(10MC SWP)
213MC
(10MC SWP)
Not used
213MC
(10MC SWP
207MC
(10MC SWP)
201MC
(10MC SWP)
195MC
(iOMC SWP)
189MC
(IOMC SWP)
183MC
(IOMC SWP)
177MC
(IOMC SWP)
185.75MC
181.25MC
185.75MC
211.25MC
215.75MC
215. 75MC
211.25MC
215. 75MC
205. 25MC
209. 75MC
199.25MC
203.75MC
193.25MC
197.75MC
187. 25MC
191.75MC
81.25MC
185.75MC
175.25MC
179. 75MC
CHANNE1
13
8
6
6
CONNECT
SCOPE OR VTVM
VTVM
DC Probe to Pointqp
Common to chassis.
SCOPE
Vert. Amp. to Point
<@>. Low side to
chassis.
VTVM
DC Probe to PoinK^p
Common to chassis.
SCOPE
Vert. Amp. to Point
^^. Low side to
chassis.
ADJUST
A15
A16, A17,
A18, A19
A20
A21, A22,
A23
REMARKS
Adjust for zero reading. A positive and
negative reading will be obtained on
Adjust for response curve with bandwidth
shown in figure 5.
Adjust as in step 13.
Adjust for response similar to figure 6.
If necessary slightly retouch A21, A22, A23 and A17 for proper response on channel
s obtained with -3 volt reading at Point D .
8
8
13
13
13
12
11
10
9
8
7
VTVM
DC Probe to Point
^J} Common to
chassis.
SCOPE
Vert. Amp. to Point
<K>. Low side to
chassis.
VTVM
DC Probe to Pointful)
Common to chassis.
SCOPE
Vert. Amp. to Point
^^. Low side to
chassis.
A15
A25
A26
Adjust for zero reading. A positive and
negative reading will be obtained on either
side of the correct setting.
Readjust A16, A17, and A19 for response
curve, frequency and bandwidth shown
in figure 5.
Adjust for maximum amplitude of response
midway between the markers.
Then over-
shoot the adjustment of turning the slug in
the same direction a little more than
required for maximum amplitude from the
initial setting. Adjust A19 for maximum
amplitude.
overshoot the adjustment as in step 20.
Adjust A15 to reset the oscillator to the
proper frequency.
Check all high band channels for proper
response with markers above 80%. U
markers do not appear within 80% repeat
step 14. If A19 is adjusted, the adjustment
should be over shot a small amount and
compensated for by adjusting A25 for
maximum amplitude between the sound
and video markets.
If the valley in the
top of the curves on the high channels
seems deeper than normal adjust A27 to
flatten the curve. In later productions
A27 may be fixed and will not require
adjustment.
Check the oscillator frequency for the high band channels. If the oscillator is off frequency, overshoot the adjustment of A15 and compensate for it
by adjusting A26 for zero voltage at Point B .
Repeat step 15.
Two 120ft
carbon
res.
Across antenna termin-
als with 120ft in each
lead.
85MC
(IOMC SWP)
83.25MC
87.'75MC
6
SCOPE
Vert. Amp. to Point
<^. Low side to
chassis.
Check for response curve similar to
figure 6. If necessary retouch A21, A22,
and A23 for proper response.
Check the voltage at Point D . If necessary adjust A24 for -3 vo t reading. If A24 is adjusted, turn channel selector to channel 8 and readjust A16 for
proper response.
Two 120ft
carbon
res.
Across antenna termin-
als with 120ft in each
ead.
"
85MC
(IOMC SWP)
Not used
83.25MC
87. 75MC
215. 75MC
209. 75MC
203.75MC
197. 75MC
191. 75MC
185.75MC
179. 75MC
87. 75MC
81. 75MC
71.75MC
65.75MC
59.75MC
6
13
12
11
10
9
e
7
6
5
4
3
2
SCOPE
Vert. Amp. to Point
^> Low side to
chassis.
VTVM
DC Probe to PoinKg>
Common to chassis.
A28
A30
A 31
A32
A33
A20
A34
A35
A36
A37
Check all low band channels for response
similar to figure 6, and the injection volt-
age at Point D which should be -3 volts.
Also recheck channels 7 thru 13.
If necessary adjust A15 for zero voltage as
in step 13.
Adjust for zero reading. A positive and
negative reading will be obtained on either
Turn channel switch to channel 8 and adjust A24 for proper response. When A24 is properly adjusted the curve will be slightly wider with a slightly
deeper valley at the top. Check all channel for: (1) proper response, (2) oscillator injection voltage at Point D, and (3) oscillator frequency. Make
slight touch up adjustments, if necessary. If A16 and A24 are changed considerably, retouch the oscillator frequency on all channels.
Disconnect the 39£i resistor from terminals 1 and 2 on the terminal strip and reconnect the co-ax link. Repeat steps 11 and 12 of Video IF Alignment.
17.
18.
23.
24.
25.
PAGE 11
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