"mike" wrote in message ...

On 11/10/2012 8:02 PM, wrote:
It's unlikely that there's anything digital in that FG507...unless you
want to call the trigger comparator digital.

I find that a bit hard to believe but surely is possible. Maybe I'll just
STFU now lol. And no, even if a comparator is considered digital that's
not what I meant. I guess the thing is older than I thought.

So really, what do you think is wrong with it ?

J

late 70's design.

My first response discussed the likely power supply topology and things
to look for.
My money was on the pass transistors coming unsoldered from the backplane.
He seems to have eliminated that possibility.

The symptoms were not clear. "No joy" is insufficient specificity to
provide much help. I made the rash assumption that the power light was off,
but who knows.
There are a bunch of mainframe issues. They get bent.
The fiberglass is abrasive and wears the socket and can lead to
misalignment of the contacts and intermittent contact.
The instrument is likely very simple and should be easy to figger out
with a scope.

Thanks mike. I always had a power light. The FG is still running (I will
not turn it off until later) as my project is not over and I don't want to
risk that it won't start again.

My guess is that the mainframe is OK as my other plug-ins all work fine.

The FG is repairable but difficult if there is no extender card available!