Podcasting since 2005! Listen to Latest SolderSmoke

Saturday, March 28, 2015

SolderSmoke Podcast #174:Belthorn III, BITX20(-40), Parasites, Test Gear, Hamfest, SPRAT, Flares, BITX History

SolderSmoke Podcast #174 is available:


March 28, 2015

Happy Arduino Day!
Pete's Belthorn III Transceiver (with cool color display)
Bill's BITX 20 (that used to be a BITX20/40)
AD9850 DDS added to Barebones Superhet
Jean Shepherd on Parasitic Oscillations, Obsession, and Madness
Simple Test Gear for the Homebrewer
Digital Oscilloscopes and their amazing capabilities
Dongles and other great stuff in SPRAT 162
The BIG St. Patrick's Day Solar Flare
VK6MV's Amazing Rhombic (+)
VK7XX (Dos Equis!)
A Bit of BITX History
Pete going KX3 QRO

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. hi, pete, and juliano

    i would love to add aerial analyzer like one designed by VK5JST in the list of test gear
    nice treatment of soldersmoke #174
    sarma from India

  2. Bummer of the Bitx40.

    A good IF is 8.192mhz with a 15.360Mhz LO can be done using crystal for LO (Use two in super VXO).

    Order of equipment obtainium...

    Decent soldering iron/station
    Good multimeter (ohms, Volts, amps).
    AADE LCII parts is not parts.. measure them.
    Frequency counter simple is good, to 50mhz atleast
    Scope, a good one. Rigol adds a lot to capability.

    Oh a spec analyser is just that if you add a tracking generator now you can do SNA(scalar network analyser).

    However... The one device I use is dirt simple.
    A 50 uA meter, two diodes in voltage doubler and two caps.
    Whatsitdo, RF detector. The diodes are right on the back
    of the meter. One cap is across the meter and the other is from the diodes as a "probe". If the meter can be moved there is RF, if an amp with no input moves the meter its oscillating, if the oscillator doesn't move the meter its defunct. It was my first RF measuring tool some 50 years ago and I still use it.


  3. Sinc L/C = VFO and Crystal = VXO..

    how about DDS chip = DXO?

  4. Bill & Pete,

    I am a longtime listener and look forward to your podcast each month! I had to comment on Pete's crystal radio project. When I was six or seven in the fifties, my dad and I built a crystal radio and had the same issue... not enough gain. Dad suggested we build a transistor amplifier. As you told the story, somehow I knew that you too would say you used a beautiful metallic purple-blue Rayteon CK722! My amp was in a clear plastic box and I loved showing my friends the cool, magic "transistor". Now, back to my K2, KX3, Raspberry Pi and Arduino!

    73, Mike, W8NWA (My dad's first call from the 30s)


Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column