HP 3562A, Service Manual

Page: 365 / 570

FAU LT I SOLAT ION
MOD E L 3562A
7-2
Ve rify
To understand the self-cal ibration process, refer to paragraph 7-1 7,
"Self-Cal ibration".
To understand the instrument's operation and signal mnemonics refer
to Section V I .
Use the osc i l l oscope waveforms i n paragraph 7-1 3 to verify correct
operation at various test poi nts in the instru ment.
Troubleshooting Hints
1 . I nterm ittent cab les can cause hardware fai l u res.
2. Noise or spikes on power su ppl ies can cause instru ment fai l u re.
3. I ncorrect bias su pply voltages can cause false diagnostic messages.
4. Use front panel diagnostics to isolate the problem before extensive troubleshooting.
5. It is possible that one circuit board can load another circ u it board caus ing the wrong
one to appear to be defective. This appl ies to both analog and digital signals.
6. Whenever possi ble, d ivide the ci rcuit under test in half (half-splitting).
7. If the name of a non nu merical key or 'E NTRY Not E nab led' appears in the lower left
of the disp lay immed iately after the power-u p routine, there may be a stuck key or
shorted trace on the keyboard (go to 8-1 5).
8. Do not remove any assembly from the instru ment with the power on. There are several
sensitive components in the instru ment that m ay be damaged by power supply gl itches.
9. To stop the instrument cal ibration, press soft key S8 (last soft key) just after the d is play
appears. Note: TEST ALL and S E L F TEST may not be val id if this key is p ressed before
these tests are done.
1 1 . Measu rements i n this section are only approximate (usually ± 1 d B or 1 0 % ) u n less
stated otherwise.
NOTE
FFT Gl obal I nterface . . . FA I LS
This failure message may occur if the instrument is internally set
with unknown parameters before runn ing the test (th is can be
caused by various measurement setups). Before runn ing any of the
FFT self-tests, press the
HP
3562A keys as follows:
PRESET . . . R E S ET