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Saturday, May 18, 2013

SolderSmoke Podcast #152 Special Digital Edition

SolderSmoke Podcast #152 is available at


May 18, 2013

-- SolderSmoke's WWV Advertising Campaign! 
-- Bands Better -- Working DX!
-- Shack and Shed reorganization
-- Arduino Madness!  CW Beacon Machine!  DDS Sig Generator! (see video above)
-- Breaking and Fixing an Arduino
-- Reverse Beacon Network
-- The Cult of Arduino: QRP Computing with Italian Charm
-- PSK-31 and JT65 with Homebrew DSB Rig
-- SolderSmoke Book Corner:  Hollow-State Design!  Getting Started With Arduino!
-- Massimo Banzi has THE KNACK!
-- MAILBAG:  AA1TJ, G3RJV, AL7RV (now W8NSA), others...  

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20


  1. Bravo Arduino! The keyer is the perfect way to get started. Ladyada (rhymes with cicada) writes the best Arduino tutorials on the web. Best tutorial book is Getting Started with Arduino, and the super reference, packed full of code for every feature, is the Arduino Cookbook. Enjoy!

  2. I too have been playing a little with the Arduino - doing some useless "ham radio related" stuff.

  3. Thanks for the heads-up on those AD9850 DDS cards, and AD7C's excellent site. I've always wanted to fool around with DDS, but it was never anywhere this cheap or easy. I ordered two, since they can tune together with one's phase shifted 90 degrees, for quadrature I/Q mixers like KK7B's radios.

  4. You should know the last major Cicada hatching was in 2004. I'm pretty sure that's not 17 years ago.

    They are -very- loud. I was driving down I95 toward Baltimore, and heard them in the car, at road speed, with the windows up.

    Enjoy. I was picking bodies out of the car grille for weeks.

  5. >> they can tune together with one's phase shifted 90 degrees
    Mike, I ordered two for the same reason, but there are some roadblocks.

    To get this to work right you'll need to do 2 things:

    1) feed them from the same REF_CLOCK. This means removing the 125Mhz oscillator from one of them, and feeding it from the oscillator on the other (or feeding both from a separate common source).

    2) Triggering the FQ_UD on both and the same time, and (here is my sticking point) synchronizing the FQ_UD with the REF_CLOCK, likely by feeding FQ_UD from your microcontroller through a D-type flip-flop that is itself clocked with REF_CLOCK.

    If you don't do #2, you have a chance of FQ_UD being processed on different REF_CLOCK cycles, which would give you a large phase error between the modules.

    See page 3 of http://www.analog.com/static/imported-files/application_notes/AN-587.pdf

    It is handy to have 2 modules anyway, and they are cheap enough. I should have ordered 4, so I could try to hack a pair for quadrature, and have two left if I messed up...

    Paul - K0EET


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