Agilent Technologies 8564EC, Service Manual

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442 Chapter 9
IF Section
Performance Test Failures
Scale Fidelity Performance Test
Failure of this performance test indicates a possible problem with the
A4 assembly:
• If the Linear, 5 dB/div, or 10 dB/div scales are out of specification, the
fault is most likely on the log amplifier assembly (P/O A4).
• If only the 1 dB/div or 2 dB/div scales are out of specification, the
fault is most likely on the A3 interface assembly.
Resolution Bandwidths Performance Tests
Most resolution bandwidth problems are a result of A5 IF assembly
failures. The resolution bandwidths are adjusted in the following
sequence using 300 kHz as the reference: 1 MHz, 2 MHz, 100 kHz,
30 kHz, 10 kHz, 3 kHz, 1 kHz, 300 Hz, 100 Hz, 30 Hz, 10 Hz, 3 Hz, and
1 Hz. The 3 Hz and 1 Hz bandwidths are not available with Option 103.
If the IF adjustment routine encountered an error, the previously
adjusted resolution bandwidths should be working properly and default
DAC values are used for the remaining resolution bandwidth settings.
If the IF bandpass adjustments and the automatic IF adjustments fail
to bring the resolution bandwidths within specification, troubleshoot
the A5 IF assembly.