Hi Mark & everyone...
Got the same question from one or two guys at Visalia last week. In most
practical amplifiers, including the ALPHAs 87A, 89, and 91B, the tank (pi)
"Q" tends to be a bit higher on 10 & 12M than on lower bands, resulting in
correspondingly greater circulating current. Also, the rf resistance of a
given size connecting wire or strap increases with freq. The result is
somewhat greater heating of the conductor from the pi coil to the
bandswitch on 10/12M than on the lower bands.
But wider strap is harder to connect neatly to the switch lug, so we attach
a small copper heat sink to the 10/12M tap-strap. It's probably not
necessary, especially since we use silver-bearing solder for high current
rf connections, but it never hurts to have a little extra margin.
73, Dick W0ID
-----Original Message-----
From: Mark S Graalman [SMTP:wb8jkr@juno.com]
Sent: Monday, May 04, 1998 5:55 PM
To: AMPS@contesting.com
Subject: [AMPS] Alpha 87
I've got a question about the newer Alpha's,
In the pictures I seen of the unit it appears
that what looks like the lead from the bandswitch
to the 10 meter tap on the tank inductor has a
triangle piece of metal right in the center of the lead.
I can't figure out for the life of me what the heck it's
for. Any hints?
Mark WB8JKR
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