You will also have to change the plate tune cap to one of lower value plus
change the value of padding cap on 40 meters...Heath really wanted the favor
of the FCC when they designed the 221....Made it very difficult for the
"Criminal Band guys to adapt to 11 meters.
Jim, K7RDX
----- Original Message -----
From: <W0YR@aol.com>
To: <kg7da@foxinternet.net>; <amps@contesting.com>
Sent: Wednesday, May 08, 2002 2:46 AM
Subject: Re: [Amps] Adding 10 meters to a SB-221?
> Hi Marty,
>
> I, too, have an SB-221 which is still "cherry."
>
> First, you'll have to take out a trap in the input circuit which will not
> pass anything above about 25 mhZ.
>
> A second problem is that there are not enough positions on the band
switch,
> but if you're willing to skip 15 meters, you can make out. If you really
> watch for them, sometimes band switches can be found, or another with 5
> positions can be subsituted.
>
> The third problem is the input matching network and you'll have to start
from
> scratch on that. Also, you have to change the input band switch.
>
> Fourth, you'll have to find or make a 10M inductor, though that should not
be
> a big problem.
>
> All in all, it's just a big mess and you will pretty much ruin the re-sale
> value of the amplifier. That's why I haven't dove (or diven? HI) into the
> project.
>
> If you do, please share your results with the rest of us trepidacious 221
> owners.
>
> 73
>
> Mike
> WØYR/4
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