On Tue, 29 Jul 2003 22:01:54 -0700, "Dan Levin" <djl@andlev.com>
wrote:
>At the risk of demonstrating to the world my complete lack of undestanding
>of high power amplifiers, is it correct that this kit basically senses input
>RF,
>and biases the tube to cut-off in the absence of input RF - thus reducing
>the
>"circulating currents"?
_________________________________________________________
I have not used the EBS-1, but from your description above, it reduces
"idling" current, not circulating current.
I doubt if this would be of any practical value in your case, since in
heavy-duty contesting, there are few if any "idling" periods anyway.
On the other hand, it can't hurt as long as it switches rapidly.
Of more concern in the AL-1200 is the tank coils, especially the 160
and 80 meter ones. I had an AL-1200 about ten years ago and at that
time they were undersized, at least for RTTY operation. They may or
may not have been improved since then. Twice I had them get so hot
while CQing that once the solder joint tap let go and once the coil
itself melted into a spiral. A replacement coil was $26 as I recall.
The tube also blew while under warranty and was replaced no charge.
That was RTTY, however, and I suspect CW or SSB would not be a
problem.
As you might guess, I'm not enamored with the AL-1200. Since then
I've had an Alpha 91b and a Command HF-2500. Both are much more
heavy-duty.
--
73, Bill W7TI
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