17. Tune the source 1 kHz above the fractional N frequency. The voltage measured on the
DVM should be approximately -12 Vdc.
18. If the DVM reading does not change, the Al4 frequency control assembly is defective.
Reconnect W32 to A14J501. Replace the jumper on A14J23 to the NORM position.
SYNTHESIZED
SWEEPER
DIGITAL VOLTMETER
TEST CABLE
A14J2/3
PIN 3
A14i501
A14J23
PIN 1
Sp127e
Figure 11-3. YTO Loop Test Setup
Check Al5 RF assembly (steps 19-25)
19. Disconnect W34 from A15UlOOJl and disconnect W32 from
A15JlOl.
20. Connect a frequency counter to
A15JlOl.
Connect a high-frequency test cable from an
HP
8340A/B
synthesized sweeper to A15UlOOJl. See Figure 11-4.
21. Connect a BNC cable from the spectrum analyzer 10 MHz REF IN/OUT to the
HP
8340A/B
FREQUENCY STANDARD EXT input.
22. Set the HP
8340A/B
to the following settings:
Frequency standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . EXT
Powerlevel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -5dBm
23. Set the spectrum analyzer to the following settings:
Span . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OHz
Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Single
24. Set the spectrum analyzer and HP
8340A/B
frequencies to the combinations listed in
Table 11-5 and press
(SGLSWP)
on the spectrum analyzer.
Synthesizer Section
11-l
1