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Electronics => Repair => Topic started by: blueagle91 on August 21, 2016, 01:06:29 pm

Title: Wavetek DM23XT not meausring
Post by: blueagle91 on August 21, 2016, 01:06:29 pm
Hello :)

So i have this old Wavetek andi used it a lot. Excelent DMM, not autorange but fast reliable, well reliable thats a question mark there isnt it :)

So bout a month ago, i just turned it on wanted to do some measurments, and well it wont measure. It stuck, it changes all the ranges, displays correct units, moves the decimal point, turns on off, changes AC DC, but it wont measure nothing.

For an example if i put it in diode/continuity check, its stuck at .220 and thats all. If i put it in MegaOhm range, it counts up like its charging a capacitor.

Volts are zero all the time. Anyone had this problem, fuses are ok, inputs do have nice clean contacts, probes are good.

I just hope its not something big, cause i really like it, i have other DMM`s, but i really love this one.

Thanks all the best
Title: Re: Wavetek DM23XT not meausring
Post by: retiredcaps on August 21, 2016, 04:19:25 pm
I just hope its not something big, cause i really like it, i have other DMM`s, but i really love this one.
Can you post clear focused pictures of the pcb (both sides) so we can see the inside?  You may have a problem with one or more of the input protection components?
Title: Re: Wavetek DM23XT not meausring
Post by: Jacek_Paw on August 22, 2016, 07:16:44 am
I saw similar problem with Wavetek multimeter and it was caused by one of the traces under the knob. The material was to soft and it got pounded on the pcb and made a short with another trace. As far as I remember one of the traces was responsible for the reset and while it got shorted uC wasn't able to work.