开云体育

I tried to use up some parts on hand for projects this winter.? This radio has a QRP-Labs arduino shield, a QRP-Labs receiver module, Teensy LC controller, Nokia display, Rtc clock for time keeping, qrp labs OCXO.? Added not in the picture is USB sound card, USB hub, laptop running HDSDR and WSJT-X.

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It runs standalone WSPR on a single band or a band group.? And it runs digital modes using the type of modulation that the QDX uses - samples audio and sets the frequency with the Si5351.? It runs on 5 volt USB for power.

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At 200 mw, FT8 contacts are a bit challenging.?? I am not sure what the future of this project will be.? With a bit more power out it would be a very usable digital modes radio.

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This radio is a solar powered WSPR transmitter.? It has a QRP labs arduino shield, PIC16F690 controller, a dds module, a high side switch to control power to the transmitter parts.? It uses a WWVB receiver from Universal Solder for timekeeping.

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I found that the DDS draws considerable power even when powered down ( the 125 mhz oscillator I think ).?? With the high side switch the DDS is only powered when transmitting and it drifts about 16 hz over two minutes.? The frequency is measured before and after the transmission to determine drift. ?? A linear adjustment to the DDS frequency is added with each wspr element transmitted.?

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The WWVB signal is received by setting the pic16F690 UART to 10 baud.? This works really well with the UART hardware doing all the WWVB signal timing.? If you look at the WWVB signalling protocol you will see it looks just like serial data from a UART.

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A work in progress... It uses the front panel from a QCX.? The controller is a 68HC11 SBC from Axiom.? My daughter used the board for a collage course and gave it to me many years ago.

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