Agilent Technologies 856290216 Analog Zero-Span Problems Non-Option, Lo-12 Controller Section

9.The waveforms should look like those illustrated in Figure 10-10. 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).

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/div 0 . 0 0 v 1 . 0 0 ms/div 0 . 0 0 0 s

J201-14

UZIBD-14

S K 1 9 9

Figure 10-10. Delta Y Waveform

Analog Zero-Span Problems (Non-Option 007)

1.On the spectrum analyzer, press (PRESEI), [Wi, ZERO SPAN , (e), (iJ, [ms, LCAL),

MORE, and CRT ADJ Pattered .

2. Set an oscilloscope to the following settings:

Amplitude scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 V/div Sweep time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..lms/div Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . External

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

4.The display should be similar to Figure lo-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, 1 of 4.

5.The sweep input from Jl-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.

6.In Figure 10-11, there is no synchronization between DEFl and the video patterns X POS and Y POS when DEFl is TTL high. The Y POS level when DEFl is low is the Video In level.

lo-12 Controller Section