Wiltron 561 Scalar Network analyser ramp error

[matt09]

Hi all,

Recently acquired this bit of kit, not really my area of expertise so unsure where to go with it.
I have substituted the dead NiCad battery but I still get the error:

TEST FAILED
(A4) warning - ramp not calibrated

CH2 LED flashes on power up which does indicate an A4 - sweeper interface error.
Does anyone have experience with kit of this era?
Have glanced through the service manual but it doesn't mention this and cannot find a copy of the regular manual.

Cheers

[matt09]

Anyone?

[matt09]

bump!

[matt09]

New years bump, someone must have used these?

[matt09]

Please guys   

[nonlinear]

Ramp is a sawtooth frequency sweep signal (usually 0-10V) generated either by analyzer itself or by external frequency sweeper.

In your case there are 2 variants:
1. Analyzer is configured to use external ramp and misses it.
2. Internal ramp generator is faulty.

Look through the user and service manuals (both are freely available - Google for them).

[matt09]

Yes I know the board is for sawtooth generation, I've looked at both manuals but neither seem to give specific information regarding a procedure to verify the unit via test points. This would imply there is a third type of test and validation manual, though I can find no mention of it.

[nonlinear]

Ramp generation is a part of the scan cycle.

So at least is the scan cycle itself working?
Any LED blinks each cycle?
Any blank/channel_switch strobes on the outputs?

Will analyzer accept external ramp signal (0-10V with potentiometer)?