KIKUSUI cos5020 Scope Service Manual Urgently needed

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi

I have a KIKUSUI cos5020 20Mhz scope and its really acting funny when measuring signals and setting the time base to anything over 20ns > to get a better view of a wave dv/dx it cannot get a lock on the wave and just goes wild like the time base is messed up

KIKUSUI cos5020 20Mhz (Not mine just in case you wanna know what it looks like)
An externally hosted image should be here but it was not working when we last tested it.



Does anyone have an idea where i can find a Service Manual for the scope i really will appreciate anyone’s help even a guide as to why the scope is behaving like this ive tried everything :(

P.S i wish i had cash for another scope but i just dont have they too expensive so i have to work with this one.

Thank you in advance.
 
I used to work on scopes like this long time ago (we maintained more than 2300 different models of test equipment at the time) and they were nice scope when they were working ;) They were meeting their specifications by the teeth, unlike TEK, and some of the switches (attenuator and time base switches) were already intermittent 20 years ago. It is likely the case with your problem.
 
I agree completely, they are not bad 20Mhz scopes.

I repaired/overhauled a pair of them for a chap about a year ago. The switches are normal consumer grade stuff of 20 or so years ago. I had to remove the whole front panel and desolder all the switches seperately to give them a good clean.

One of them had been fiddled with and it took a bit to get the attenuators back in line, someone had added additional variable caps and resistors of probably at least 50 years vintage. Nice. Ive got some photos around here somewhere..... Just looked only photos of the bent cases and handles after DHL had them.

The trigger on them is a bit strange if your used to TEK or HP stuff. I would say your fault is almost definately dirty switches. Its not too bad a job just takes a while.

Cheers Matt.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.