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tm

"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.

There is no processor in the FG507.

The main capacitors are in the mainframe. This unit does not use the AC
voltages from the mainframe.

One thing to take a look at is the IC sockets. If they are the TI type, it
would be the first thing to check as it is a known issue.

You might google for information on that problem.

Have fun,

tm