EEVblog Electronics Community Forum

Electronics => Repair => Topic started by: dsw8191 on February 27, 2020, 07:48:24 pm

Title: Tek 2236 aberrant trace
Post by: dsw8191 on February 27, 2020, 07:48:24 pm

I've acquired a Tektronix 2236. It works but there is a distortion in the traces even when the inputs are grounded (see IMG_1095).  The degree of distortion is dependent on Y position - worse when the trace is above mid CRT.  Both channel traces superimpose when moved to the same Y position.  The X position of the distortion is independent of time base setting.

I've searched the forum for a similar problem without success.  Hope someone wiser than I can provide an explanation for this.

Title: Re: Tek 2236 aberrant trace
Post by: pbarton on February 27, 2020, 10:19:57 pm

My vote, CRT is damaged beyond repair, possibly the scope has been dropped.
Good news, the X and Y electronics are fine.

More advice if you scroll half way down this page...
https://www.sphere.bc.ca/test/tek-parts/tek-info.html (https://www.sphere.bc.ca/test/tek-parts/tek-info.html)

and another one...
https://www.eevblog.com/forum/repair/tek-2211-crt-weirdness/ (https://www.eevblog.com/forum/repair/tek-2211-crt-weirdness/)