As the previous poster notes, Ramsey.
Though You are not allowed to view links.
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The only real DIY transmitter I knew of was the one created by You are not allowed to view links.
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He links to the a new You are not allowed to view links.
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But I don't think I'd want to have a production device on a breadboard, so you could go to quite a bit of trouble building a perf board that accepted something like a You are not allowed to view links.
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HTH.
\dmc