Exciter Alignment; Pretest; Voltage Measurements; Program Tune-Up Channel - Viking 242-2009-632 Service Manual

J201
2
1
TP3
TP4
U206
R261 R264
8 5
4
1
R284
Z213
TP5
L231 L225
L211
L207
L209
L229

7.3 EXCITER ALIGNMENT

Refer to Figure 7-2 for component locations.
Refer to Figure 7-10 for equipment needed and setup
diagram.
WARNING
SAFETY MEASURES ARE DISABLED IN TEST
MODE. ALARMS ARE ACTIVE. HOWEVER,
FEATURES SUCH AS THERMAL SHUTDOWN IN
THE PA ARE DISABLED.

7.3.1 PRETEST

1. Set TCXO modulation adjust R425 fully counter-
clockwise.
2. Connect the power meter to J402.
3. Connect OCXO to J403.
NOTE: 2000 Series OCXO must be powered up for 1/
2 hour or longer to stabilize frequency.
20
19
TP6
Y201
TP1
L224 L223
L205
L206
Figure 7-1 RECEIVER ALIGNMENT POINTS
ALIGNMENT AND TEST PROCEDURES
TP2
U208
L204 L203

7.3.2 VOLTAGE MEASUREMENTS

Apply power to the Exciter by plugging the 20-
pin cable from the RF Interface Board into J401.
Measure the voltages at the following pins.
U406, pin 1 +12V DC 0.4V
U405, pin 1 +5V DC 0.2V
U404, pin 7 +3.5V DC 0.1V

7.3.3 PROGRAM TUNE-UP CHANNEL

1. Program the Transmit Channel.
2. Use the "Turn on carrier" button to key the Exciter.
3. Tune VCO helical L404 for 4.5V 0.05V on U403,
pin 6 (TP1).
4. Measure the Power Output of the Exciter at J402.
Reading should be +17.5 dBm 0.5 dB.
5. Use the "Turn on carrier" button to unkey the
Exciter.
7-3
A006
L220
L202
L201
March 1999
Part No. 001-2009-600