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Re: Autotuner for Drake R8B?


 

Bill . . .


On Thu, 11 Jan 2024 14:02:03 -0800, "William Rowe" <wmrowe@...> wrote:

Instead of getting up and walking to my radios, I would love to have an autotuner to do the work for me. Any suggestions?

All of the auto tuners I know of require a small signal to be transmitted so
that the SWR sensing circuit can work with the tuner logic to find a low SWR
match. That would require a license to transmit on the frequencies of interest.
Even with a ham license, you would not be allowed to transmit on SW broadcast
frequencies.

However, you could use an active preselector like the MFJ-1045C. A passive
preselector will introduce insertion loss. Even an active one introduces the
same loss, but it will have a preamplifier built in to compensate for that and
possibly to boost signals a bit compared to now using one.

Whether this would be worth trying is a question I can't answer. I think you're
fine with what you have now. An auto tuner requires a signal, which you can't
provide since you're not licensed on the frequencies of interest. If you have
plenty of gain and don't have trouble pulling in your stations, then I doubt a
preselector would help. A manual tuner, like an auto tuner, would introduce
insertion loss, as would a preselector (though an active preselector would have
a preamp built in to compensate for this loss).


Donald KX8K



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