>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...
The padding C is for 80m-loading. The tune C on my SB221 was identical
to that in my SB-220.
>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.
Putting a SB-221 on 27MHz involves wiring around the CB filter; moving
the 15m tap on the tank L; and installing a Q=2, 27MHz tuned input in the
15m slot. Elapsed time c. 20min. Any gen-coverage ham transceiver that
delivers 140w will drive a SB-22_ to full suds.
>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
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>
>_______________________________________________
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>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps
>
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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