"Alec S." wrote in message ...
Thanks for the info guys. There’s good news and bad news.

The good news is that I now know what the problem is, and if I’m lucky
(which
unfortunately history has shown otherwise), it may be easily fixable.

The bad news is that you guys were both right and wrong about it being a
7805,
not a 7905. You’re right because that is indeed what is supposed to be
there.
You’re wrong because that’s not what’s currently there. When I posted this
a
month ago, I was advised to remove the three suspect components (the
voltage
regulator, a power resistor, and a cap near the bottom of the board) to
find
what was causing the short. I did so and found the short (it was B52
between the
power resistor and regulator). I removed B52, which resolved the short,
but when
I was putting the three components back, somehow I put in a 7905 instead
of the
7805 (I’m still looking for the 7805 right now).

I guess it makes sense that it’s not working now. I don’t suppose that
I can
expect it to work when I put the correct one back can I? Would having a
7905 in
there (while on) have killed the board?


--
Alec S.
news/alec-synetech/cjb/net


Ah yes, I rember the original thread now, and the problem coming down to
that component, and why its descriptor should have been a "B". I think we
eventually decided that it was probably a cap, and the "B" was for " B -
ypass".

It is highly unlikely that the board will have suffered any damage, although
the 7905 may have. Usually, if you hit the input of one of these monolithic
regulator ICs with the wrong polarity for its type, it just sighs gently,
and ignores you, so get the right one back in there, and fingers crossed ...
:-)

Arfa