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Products => Test Equipment => Topic started by: EncomLab on March 13, 2018, 09:51:45 pm

Title: Used Tektronix 2235A - things to check for?
Post by: EncomLab on March 13, 2018, 09:51:45 pm
Picked these up today from a University for nearly nothing - anything I should check for or be aware of with this model?  I've used a 2 channel analog scope before but its been years.

(https://i.imgur.com/i9kHsyn.jpg)
Title: Re: Used Tektronix 2235A - things to check for?
Post by: David Hess on March 15, 2018, 04:22:01 am
The 2235A was the final refinement of the 2 channel 22xx series so many of the problems with the earlier models were solved.  The late production year also means these are less likely to have worn out aluminum electrolytic capacitors in the power supply.  So if it works, then it works and I would not risk borrowing trouble by messing with it unnecessarily.

Check the basic operation of all of the controls.  Check the CRT performance for double peaking and blooming at high intensities.

I do not remember if the 2235A has a fan or not but if it does, check that it is working and not noisy.  The line side X and Y EMI filter capacitors are known to fail with age and should be replaced *if* you have to gain access to that area for other reasons.  The previously mentioned aluminum electrolytic capacitors are nearing the end of their life.
Title: Re: Used Tektronix 2235A - things to check for?
Post by: tecman on March 15, 2018, 06:38:03 pm
Nice catch.  Curious what you paid for them ?

paul