[AMRadio] antenna tuners transmision lines and more

Mike Dorworth, K4XM k4xm at arczip.com
Tue Apr 25 21:21:04 EDT 2006

----- Original Message -----
From: "Donald Chester" <k4kyv at hotmail.com>
> I recall there was a Central Electronics rig that had a no-tune broadband
> output network with a tube type final.  They sealed the whole thing in
> something like epoxy, and gave no technical data on how it worked.

Yes but it was a patented device and the patent number was shown. I sent for
the patent disclosure and built the coil as presented. It worked perfectly
and I made measurements that showed it's own impedance to be 25 ohms and it
would easily match 25 to 100 ohms 2:1 SWR. Mine was for a single 813 final.
As I recall the network was in some ceramic that was nearly impossible to
open short of an A-Bomb and many wondered what was inside since no-tune was
a mystery at that time.. Mike

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