[volt-nuts] HP 3457A Arrived

[Joseph Gray]

I got the OK to open the 3457A. I didn't see anything that was obviously
loose or broken. I reseated all connectors and also the socketed ROM. It
now powers up and passes self test (at least twice so far). I did all this
over lunch, so tonight I will be taking an even closer look at things.

While I had it open, I looked it over a bit. All the chips are dated late
1991 or early 1992. The old optocoupler has been replaced by two chips that
span the slot in the board.

The battery looks like it is probably original. The solder connections
don't look re-done. The battery is a Panasonic BR-2/3AE2SP. The tab on one
end has one point, the other end has two. Mouser sells these for $5.24.

Joe Gray
W5JG



On Wed, Aug 21, 2013 at 5:34 PM, Joseph Gray <jgray at zianet.com> wrote:

> Boy, I have the worst of luck. I think Murphy follows me around. I won't
> bore you with the details about my recently dropped by Fedex service
> monitor and major repair cost.
>
> The 3457A arrived. Other than missing feet, it looked in decent condition.
> I powered it up and that is when things went wrong.
>
> The first several times, on power up, I got the Address display and the
> beep, but instead of going to DCV, it displayed PASSED, with an occasional
> FAILED. It would do this seemingly forever.
>
> Once, it powered up normally, then froze. Another time, it powered up
> normally and I managed to read the error code (1 - Hardware error) and the
> auxilliarly error (1 - Isolation error durring normal operation).
>
> Later, it would power up and immediately display FAILED. At this time, I
> happened to lift the front of the cabinet and saw that FAILED and PASSED
> would randomly alternate on the display. Something is definitely loose.
>
> I would have already opened the DMM up, except the seller applied
> anti-tamper labels to the case screws (I have a 30 day warranty). I have
> sent all of this information to the seller. Hopefully, he will authorize me
> to open the case and see what is what. Otherwise, I have no choice but to
> return the DMM.
>
> Joe Gray
> W5JG
>
>