The U3S is a many-mode beacon transmitter that offers some amazing functionality, especially given its low price.
It is primarily used as a WSPR transmitter but is also capable of Hellschreiber, Opera, QRSS, all of the JT modes and more; plus automatic band-switching and GPS control of frequency.
I built one about 14 years ago and I still have it today; in fact, it's operating on 20m WSPR as I type.
The QMX+ has become the QSX and now the U3S.
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Amazing!
ReplyDeleteSverre/LA3ZA