[time-nuts] HP-5335A Fail Code

[Magnus Danielson]

On 03/27/2011 11:56 PM, Gordon Batey wrote:
> Thanks for your interest Magnus.  I am entering the diagnostic
>
> start codes as you mentioned at the bottom of your email but all
>
> I get are a series of seemingly random numbers.
>
> I do have a second similar counter to refer to, so that helps.
>
> The manual seems to indicate that the problem may be in the
>
> MRC or A4U7. Not I need to see how to see which one.

Hope for the A4U7, as it is much more likely to be replaceable.

Also consider that the MRC (A4U6) is sitting in a IC holder, so oxide on 
any of the data bus pins for instance would help to distort the picture. 
Signature analysis is what I would attempt here. Not many have those 
toys these days. I recently got one from a clean-up, and realized what 
it was. :)

Cheers,
Magnus