First Name Bob
  QTH Freeport, IL
  Prior Call(s) ⇰ KE∅T
  Other interests ⇰  Recumbent Biking, Paddling, Camping, Homebrewing, Radios old and new from tubes to SDRs
  Email W9RAN
   My External Web Site  vintage gear


   The Spilsbury and Tindall PRT-20

    You may have heard me check into the MCRN with this one watt rig. It is a Spilsbury and Tindall PRT-20. They were used as
    "bush radios" in Canada where Spilsbury is located (Vancouver area) and for logging, oil exploration, forest-fire fighting, etc
    in the late 50s-early 60s until SSB versions replaced them. Click here for more info and better pictures. Bob  (page opens in new browser window)


   Virtual Radar from a Digital TV Dongle

    An article published in QST (January 2014). It appears on page 38 and is titled Virtual RADAR from a Digital TV Dongle. You can click here to go directly to an online version of the article.  (page opens in new browser window)
   The All American 75


    The October 2013 issue of Electric Radio Magazine includes my article showing how to convert a basic "All American 5" broadcast radio into a simple 2-watt 75 meter AM transceiver, named "All American 75." MCRN members as far as 300 miles away have heard its Heising-modulated QRP signal.

    The AA75 conversion consists of adding an external power supply to eliminate the hot chassis shock hazard and building a simple crystal controlled transmitter using a 35L6 that replaces the original rectifier tube in the series filament string. Re-tuning the receiver from the BC band to 75 meters provides about the same performance as an S-38 type receiver which is good enough to hear any station that can receive the AA75s QRP signal.

    I was motivated to try the AA75 conversion after finding an AA5 radio with a hopelessly broken plastic cabinet in an antique shop for $5. As a result, this rig is housed in a homebrew cabinet made of scrap wood and plastic (note how the dial has been carefully calibrated for AM operation!) I hope others will be motivated to try similar conversions and with their own innovations. Since the basic AA5 circuit was used by hundreds of manufacturers, the AA5 was possibly the original Open Source Design!

    Unfortunately, a couple of errors crept into the 35L6 transmitter schematic that appears on page 19 of the article, and I urge anyone wishing to give this idea a try to use the following corrected version of 10/13 instead of the one published in ER.

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  Last update March 11, 2017