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July 10th 03, 05:27 PM

In article , says...
"TC Dufresne" wrote in
:

Hi:
I am having a problem with a "Simple Receiver for Beginners". It is
from a design that was featured in an old (1981) ARRL handbook. It is
a DC receiver, looks like alot of fun, but it isn't fun now.
Here is the problem.

1) No oscillation! I can't find it (the VFO) on my DX-398 receiver at
all, or on my Radio Shack freq counter.
2) The power (+ side) electrolytic is supposed to be a 500uF, 16 volt.
I am using a 470uF 35 volt. It gets really hot!! Short somewhere?!?!?!

The VFO is REALLY simple, it has one transistor and about 7 other
parts. I can't seem to see what is wrong, and I have tried.

I would sure appreciate some Elmer'ing here!
ANY help would be much appreciated. I have the above mentioned tools
at my command, a multimeter, and an old Heathkit "scope. (which I
really don't know how to use.

Any chance?
Thanks in advance,
Tom
KCØGXX

Gotta be a short somewhere. Filter caps ain't supposed to get hot, and
yours is over rated to begin with.

and when you run an electrolytic at a different WVDC than it's rated at,
you can't be sure the capacitance is the same as marked on the can. but
it should still filter and not get hot. you'd think something else would
heat up if there was a short. should draw excessive current. unless it
blew something and is now an open, then the cap shouldn't get hot any
more.