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Products => Test Equipment => Topic started by: matt09 on December 12, 2018, 09:51:33 pm

Title: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on December 12, 2018, 09:51:33 pm
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
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on December 14, 2018, 11:23:51 pm
Anyone?
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on December 22, 2018, 03:29:14 pm
bump!
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on January 01, 2019, 02:42:50 pm
New years bump, someone must have used these?
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on January 04, 2019, 06:31:42 pm
Please guys   :-//
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: nonlinear on January 05, 2019, 11:37:54 am
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).

Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: matt09 on January 06, 2019, 08:14:46 pm
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.
Title: Re: Wiltron 561 Scalar Network analyser ramp error
Post by: nonlinear on January 07, 2019, 04:57:30 pm
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)?