HP 8562E, Service Manual

Page: 318 / 482

Because the cal oscillator circuitry on the A4 assembly is such an integral part
of the IF adjustment, always check this assembly first, before checking the rest
of the IF Section. A faulty cal oscillator can cause many apparent “faults” in
the rest of the IF Section.
Troubleshooting Using the TAM
Refer to Chapter 7, “General Troubleshooting,” for information on enabling the TAM for use
with the HP 85623 spectrum analyzer.
When using Automatic Fault Isolation, the TAM indicates suspected circuits that need to be
manually checked. Use Table 9-l to locate the manual procedure. Table 9-2 lists assembly test
connectors associated with each Manual Probe Troubleshooting test. Figure 9-l illustrates the
location of A4 and A5 test connectors. Figure 9-2 illustrates the levels and paths through the
IF Section.
A 5
I F A 4 L O G A M P / C A L O S C
,
CONNE
J 7
J 6
J 4
J 6
J 3
Figure 9-1. A4 and A5 Test Connectors
IF Section 9-3