9.The waveforms should look like those illustrated in Figure 9-10. If the waveform at J201 pin 14 is bad, troubleshoot the Y Line Generator (function block I of A2 Controller Schematic, sheet 1 of 4 in the Component-Level Information binder).

10.If the waveform at U210D pin 14 is bad, troubleshoot the Z Output circuit (function block M of A2 Controller Schematic, sheet 1 of 4).

11.Remove the jumpers.

1 0 . 0 V,‘dlv 0 . 0 0 v

1 . 0 0 ms/div

0 . 0 0 0 s

J201-14

U210D-14

S K 1 9 9

Figure 9-10. Delta Y Waveform

Analog Zero-Span Problems

l. On the HP 8560A press (PRESET), (m), ZERO SPAN , (SWEEP), 0, [ms, (CAL), MORE, and

CRT ADJ PATTERN.

2. Set an oscilloscope to the following settings:

Amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 V/div Sweep time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 ms/div Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..External

3.Externally trigger the oscilloscope off the signal at A2U207 pin 8 (LBRIGHT).

4.The display should be similar to Figure 9-11 except that the untriggered trace should show at the left edge of the screen. In these settings, DEFl causes switching between the line generators and the analog inputs (sweep and video). DEFl remains high when the CRT adjust pattern is on. Refer to function block M of the A2 Controller Schematic, sheet 1 of 4 in the HP 856OA/61B/63A Spectrum Analyzer Component Level Information binder.

5.The sweep input from 51-41 should go from 0 V to +lO V; the Video In signal should go from about 0 V to 1 V from the bottom to the top of the screen. Apply a dc voltage to A2J4, Video In, to test the circuit.

9-12 Controller Section