Saturday, December 9, 2017

SolderSmoke Podcast #201 Santa, Storms, BUILDING A DC RX, SDR, uBITX


SolderSmoke Podcast #201 is available:  http://soldersmoke.com/soldersmoke201.mp3

9 December 2017

 Santa Juliano

 Forest fires, snow storms, and an earthquake. 

 Santa arrives from Hyderabad -- uBITX in the house. 

 Radio history.  First transtalantic amateur contacts. 

 Bill's International Brotherhood Ceramic Discrete Direct Conversion Receiver Project. 
-- Goals -- Build your own receiver.  Really.  From scratch.  No cheating. 
-- How to get started.  Get parts and tools. 
-- Stage by stage. 
-- VFO first -- maybe build two. 
Bill built two already
-- Nephew is testing the first one. 
-- Polyvaricon limitations. 
-- Varactor limitations
-- Variable cap limitation.  
MEETING THE JULIANO STABILITY CRITERIA

 Understanding the F5LVG mixer

 Pete goes to the dark side with an SDR receiver. 
Pete's 800 Watt Amplifier gives him trouble. TRGHS. 

 People in the News
Cliff Stoll -- Still Passionate about Electronics
Peter Parker -- VHF/UHF  By the Bay
Yardley Beers -- Early SSB with "The Black Rose"
John Kraus -- Moonbounce without the Moon. 

 MAILBAG


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7 comments:

  1. W3JDRDecember 10, 2017 at 2:56 PM

    Bill
    I listened to your latest podcast, particularly the part about our exchange on the mixer topology. What you failed to mention was that the schematic as originally posted had a flaw and couldn`t have worked - either in LTSPICE or in practice. There was no current path to ground for the LO to produce switching current in the diodss. It turns out you had a capacitor from the mixer to ground in your actual circuit that allowed it to work, not shown in the blog schematic. I spotted this, modeled it in LTSPICE and contacted you. After you looked at your actual circuit, you confirmed I was correct and added the cap.

    Joe

    ReplyDelete
    Replies
    1. Bill MearaDecember 10, 2017 at 8:53 PM

      Right you are Joe. It needed that cap. Thanks, 73 Bill

      Delete
  2. W3JDRDecember 10, 2017 at 3:18 PM

    This comment has been removed by the author.

    ReplyDelete
  3. ryegDecember 11, 2017 at 2:26 PM

    What was the name of that pcb material supplier tha Pete mentioned in the last podcast?

    ReplyDelete
    Replies
    1. UnknownDecember 11, 2017 at 2:36 PM

      abcfab
      http://stores.ebay.com/PCB-Laminates-Copper-Clad?_trksid=p2047675.l2563
      Dale K9NN

      Delete
  4. N6QWDecember 12, 2017 at 12:21 AM

    yes abcfab.

    ReplyDelete
  5. N6QWDecember 12, 2017 at 9:06 AM

    Just wanted to comment that I am available to play Santa for special Christmas events and also provide music for weddings and Bar Mitzvahs.

    Being retired I need to supplement my income so I can buy Si5351's Arduino Nano's, Color TFT Displays and Teensy 3.5's.

    Merry Christmas and Happy New year to all.

    73's
    Pete N6QW

    ReplyDelete