I think the Drake L-7 may suffer from the same problem.
I decided to check the 30 meter output capability on mine
the other day (into a dummy load, of course). Previously I had
run the amp over-the-air on 30 meters a few times with the
output backed down to 200 W. I had never cranked up the
exciter to see what it would really do. During the tuning
procedure, I managed to get the output up to around 1000
watts before the big blue flash occured. When I opened the
case, I discovered that the 20 meter tap on the tank
coil had unsoldered itself from the lug on the bandswitch. It
probably drew an arc when it came undone. Don't know if
it was the result of a latent defect in solder joint, or if it was
just extra circulating current caused by the higher tank-Q
heating up the joint. Perhaps it was a combination.
Oh well, at least there was no major damage.
73 de Mike, W4EF..........................
----- Original Message -----
From: "Richard" <2@mail.vcnet.com>
To: "Bert Almemo" <balmemo@sympatico.ca>; "Amps" <amps@contesting.com>
Sent: Thursday, March 21, 2002 7:00 PM
Subject: Re: [Amps] SB-220 for WARC bands
>
>
> >Looking for a simple solution to modify the SB-220 to work on the WARC
> >bands.
> >
> It already works ok, except on 30m, the operating Q is a bit high.
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
> www.vcnet.com/measures.
> end
>
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>
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