ALIGNMENT PROCEDURE
Receive Board -70714000
Equipment Required:
DSignal Generator
DSensitive RF Voltmeter
DDC Voltmeter
DAF Voltmeter
1.
Connect the signal generator
to
the Receive
Antennajack. Set the deviation at ±3KHz at
1KHz. Refer to the frequency chart below.
Look at the marking on the Y301 and set the
generator
to
the corresponding ALIGN fre-
quency.
11.
Place the RF voltmeter probe tip inside the top
ofL304.
12.
Adjust VC304 for apeak indication.
13.
Adjust VC305 for anull indication.
14.
Adjust VC306 for apeak indication.
15.
Placethe RF voltmeter probe tip on the collec-
tor
ofQ303
and adjust T301, T302, and T303
for apeak indication.
Y30l
Align
CHl
CH2 CH3 CH4
Marking
171R905 170.705 171.905 171.045 170.245 169.505
207R800 206.900 207.800 207.425 206.800 206.000
213R800 212.900 213.800 213.425 212.800 212.000
2.
Adjust VR309 for 0.44 VDC across R312.
3.
Place the RF voltemter probe tip inside the top
of
L307 and adjust VC307 for apeck indica-
tion.
4.
Set the RF voltmeter to its most sensitive scale
without stray pickup.
5.
Place the RF voltmeter probe tip inside the top
of
L301.
6.
Increase the signal generator output level until
the
RF
voltmeterindication just begins
to
rise.
7.
When adjusting, reduce the signal generator
output rather then reducing the RF voltmeter
sensitivity.
8.
Adjust VC301 for apeak indication.
9.
Adjust VC302 for anull indication.
10.
Adjust VC303 for apeak indication.
3-10
16.
In the following alignment, unless othelwise
directed, adjust the signal generator output
level
to
maintain aDCvoltage
of
between 1and
1.5 volts.
17.
Set the signal generator
to
the channel 1fre-
quency.
18.
Adjust T304, T305, and T308 for maximum
DC voltage at pin 5
of
U301.
19.
Set the signal generator output
to
1 mV and
adjust T309 for maximum audio at pin 7of
U303.
20. Adjust VR302 for 140 mV ofaudio at pin 7
of
U303.
21. Set the signal generator output
to
1
~
Vand
adjust VR301
to
just extinguish the number 1
LED
on
the front panel.
22. Set the signal generator
to
the channel 2fre-
quency.