"WDØHCO - Biz" wrote in message
...
Howdy - WDØHCO Biz here ...
I am working on a moldie oldie - an old SBE-33 - one of the first
transistor/hybrid tube rigs of the mid-60's. This rig was new when "I
Dream
of Jeannie" was broadcasted on NBC - 42 years ago I think.
Well anyway that's what I remembered - the rig is fixed and working
great -
but every now and then the "PA Load" cap shorts to ground and output goes
bye-bye.
Old Faust Gonset used a trimmer cap for the PA LOAD. It's an ARCO L305
compression trimmer type - no value on the schematic but I am assuming its
180 mfd by the size.
Question is... has anyone worked on this and I am thinkin of pulling the
whole thing out and putting a "REAL" variable cap in it's place.
Opinions Please... thanks - B
Two or three ideas.
The L305 has a capacitance range from 190 to 760pF (source
http://www.arco-electronics.com/prod...e_categoryID=1
) if you are considering a replacement. Not an entirely bad idea.
Those Arco's are not hard to repair if you can get it out in your hands
to work on it. Most shorts come from mica dielectric sheets between the
plates that have cracked, shifted, or were too thin for your RF voltages to
begin with. Old Arco's from the junk box (or your favorite Ham's junk box)
are a source for new mica sheets if you find one or two that need
replacement.
I like stuff relatively unmodified, but hey, whatever you choose!
Old Chief Lynn, W7LTQ