----- Original Message -----

From: Dan

To: TekScopes@...

Sent: Tuesday, October 16, 2012 7:55 PM

Subject: [TekScopes] Re: AN/USM-125 Scope Woes

?

I have the downloaded PDF version of the service manual. I can certainly handle replacing a cap if someone can suggest which one. None of them are obvious to me. There is a 2.2uf 100v electrolytic on the output of the rectifier that was suspect so I replaced it with no result

I'm in the Nashville area...just in case.

Dan

--- In TekScopes@..., "Tom Miller" wrote:
>
> Where are you located? What model is the AN/USM-125? Do you have the service manual?
>
> Sounds like it might just have a bad power supply capacitor. You'll get some bad karma if you through it in a dumpster.
>
> Maybe someone on the list lives close to you and has the skills to repair it.
>
>
> Regards,
> Tom
>
> ----- Original Message -----
> From: Dan
> To: TekScopes@...
> Sent: Tuesday, October 16, 2012 6:55 PM
> Subject: [TekScopes] AN/USM-125 Scope Woes
>
>
>
> I have an AN/USM-125 that has always (as long as I have owned it) had issues with vertical stability. I used to be able to clean or re-seat the vertical module and it would stabilize. This time, in the process of performing the ritual, the chan 1 and 2 traces could not be positioned below the zero line on the graticule, and any input signal appeared to compress with an adjustment in vertical positioning. Now, the trace has disappeared and the +90 volt supply appears dead (at +11 volts). I do not have the guts or the tools to dig into troubleshooting the HV circuitry. Can anyone shed some light on this before the scope hits the dumpster?
>
> Thanks in advance,
> Dan
>