..Unfortunately, components that are able to handle power are scarce and
expensive.
High power means massive parts, widely spaced construction to prevent arcing
and thorough shielding between the power section and the control section.
All this amounts to a high price and big size!
It's true that you have an opportunity to exercise your ingenuity in finding
new sources of parts like, for instance, relays peeled off from air
conditioners' control boards. You can even build variable capacitors from
aluminum sheet or PC blank material. That CAN save money and cut on
frustration while trying to hunt for needed parts. But it means time and
patience.
You can go back to basics: give up the PI network and go to a swinging link
tank circuit: it has a much wider matching capability. Thanks to the
flexibility of such an arrangement, you might design a tank circuit with a
wide enough matching range, since you can control the loaded Q by varying
the coupling.
But, don't expect it to be small and cheap. Nor fast! You'll have to relearn
the old skills from one of the old books, RCA or Westinghouse or
whatever....
Wish you luck and 73:
Alex 4Z5KS
-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
Behalf Of KB0NLY
Sent: Tuesday, March 03, 2009 5:12 AM
To: amps@contesting.com
Subject: Re: [Amps] SWR & other things...
"Now if they'd just make auto tuners that had a wide range and weren't
terribly expensive."
And handle legal limit through it also.
73,
Scott
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