oscilloscope will point you to where
the signal dies. You won't see
anything at the antenna terminals,
but you should get a signal large
enough to see on the scope coming
out of the front end.
There's an address for BSR listed
on forums.djcafe.com which is
BSR, Suite 200, 18369 Eddy Street,
Northridge, CA 91325; (213)
You can try calling them or
writing to them. I would imagine that
the area code is probably something
other than 213 now (818 maybe?)
DAK does sell "closeouts," so
BSR may be out of business.
San Diego, CA
The second likely problem is a bad
capacitor in the oscillator section that
is supposed to control timing. If it is
the second case, that the whole effect
isn't working, I'm not sure I know
what to tell you. There's a possibility
that there is a bias problem, if the
oscillator feeds directly to the tubes
on the amp. I think I should point you
in the direction of Ampage, an
excellent online forum when it comes
to tube amps. It is located here
#2 Weak or no vibrato (actually it
is a tremolo) in tube guitar amps is
common. You don’t say what tubes
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[#2053 -February 2005]
I'm working on an old
Epiphone Electar Zephyr guitar
amp. It looks like it’s from the 30s
I got the amp working, but I
can not get the vibrato to work. The
oscillator is very weak.
I cannot find a schematic for it.
Does anyone have one or know
how it is wired? The output of the
oscillator goes to the grids of the
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#1 As far as I can tell by searching
the Internet, the Electar Zephyr amp
did not have a stock vibrato circuit,
but had space in the back and was
apparently a common modification,
since this is not the first time I saw
mention of it. Now, when you say that
the oscillator is very weak, do you
mean that it does not oscillate at a
proper speed, or that the effect
simply does not work well?
In the first case, there are a couple
of possible solutions. If it was, in fact,
an after-market component, it is
possible that it never worked well in
the first place. In this case, I would
advise replacing the oscillator section
with a modern, solidstate oscillator.
This shouldn't affect the sound of the
vibrato at all.
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