10. Set the HP 8560A to the following settings:
CENTER FREQ. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .300 MHz
SPAN
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..lOOMHz
11. If the 1st LO is present, a signal should be displayed at about -10
dBm
(approximately
f20
MHz from the center frequency). If no signal is displayed and ERR 334 LO AMPL is
not present, troubleshoot the A7 LODA. If no signal is displayed and ERR 334 LO AMPL
is present, check the All YTO as follows:
Set jumper A14J23 to the TEST position.
Set the HP 8560A to the following settings:
CENTERFREQ. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Hz
CF STEP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..300MHz
SPAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Hz
Connect a power meter directly to the output of the All YTO.
Press the HP 8560A’s step-up key and measure the YTO output power at each step.
Check that All
YTO’s output power is between
f9
and
+13
dBm.
Set jumper A14J23 to the NORM position and reconnect the All YTO.
12. On the HP 8560A press
(-1,
ICAL),
MORE, FREQ DIAGNOSE, and MAIN ROLLER. Note
the Main-Roller Oscillator’s frequency.
Main-Roller Oscillator’s Frequency
=
M Hz
13. Disconnect W32 from A14J501 and connect the output of a signal source to A14J501.
Connect a DVM’s positive lead to A14J17 pin 1 and negative lead to A14J17 pin 6. See
Figure
lo-
1.
14. Set the signal source to the following settings:
Power
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..0 dBm
Frequency
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Frequency recorded in step 12
15. Tune the source 1 MHz below the Main Roller frequency. The voltage measured on the
DVM should be approximately 8.2 Vdc.
16. Tune the source 1 MHz above the Main Roller frequency. The voltage measured on the
DVM should be approximately -8.2 Vdc.
17. If the DVM reading does not change, the Al4 Frequency Control assembly is defective.
Reconnect W32 to
A14J501.
10-4
Synthesizer Section
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