Podcasting since 2005! Listen to Latest SolderSmoke

Friday, May 10, 2013

DSB Digital Success!



It's ugly but it gets you there.  I finally got the little 30 meter DSB/Direct Conversion transceiver that I built in Rome working on PSK-31 and JT-65.  It features a VXO circuit from George Dobbs, an AF amplifier designed by Roger Hayward, and an RF amp chain designed by Peter Parker.  It produces about 1 watt of RF.  At first I was manually switching the rig from transmit to receive, but this got old real fast, so I built a little VOX circuit -- the AF from the sound card does the switching.  Last night I fired it up on PSK-31 and stations were calling me (including one fellow in Cuba).   Then I went to JT-65 and had a complete QSO with KT1B. Another this morning with K0ASK.  It is kind of fun to combine the simple (this rig) with the complex (the computer and these digi modes).   I find that I can work both JT65 and PSK 31 while keeping the VXO at 10.139 MHz.   

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

Wednesday, May 8, 2013

Drone Dudes



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

Monday, May 6, 2013

Homebrew Adventures with JT65


My six dollar DDS board hasn't arrived yet, so this weekend I worked on the re-build of the 30 meter Direct Conversion/DSB transmitter that I built in Rome (originally for WSPR use).  I was hoping to use this rig to make at least a few PSK-31 contacts.   But I started seeing these strange looking sigs in the waterfall.  I found out they are JT65 (JT for Joe Taylor).  So I downloaded the program JT65-HF.  I got the receiver going very quickly (it is a 40675 dual gate MOSFET followed by the audio amplifier out of Roger Hayward's Ugly Weekender RX).  The transmitter is just a two diode singly balanced modulator followed by the RF chain from Peter Parker's Beach 40 Rig.   QSOs seem imminent.


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

Saturday, May 4, 2013

Now That's A Radio Shack! JH0JDV


I was at the workbench this morning, working on a 30 meter DC/DSB transceiver.  I had the Barebones superhet tuned to white noise on 17 meters.  Then I heard a strong CQ that sounded like DX.  It was Ely, JH0JDV.   He was the only signal on the band.  We had a very nice contact, no problems at all.  I was running my normal 10 watts to a dipole.  Afterwards I Googled him.  Wow, he has a REAL radio shack!  FB Ely!

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

Friday, May 3, 2013

Making the World's Smallest Movie





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

Thursday, May 2, 2013

WA0RBR's Fun-Rig

Last night I called CQ on 20 CW (with my Arduino keying the homebrew transmitter!) and was answered by Mark, WA0RBR.   I Googled the call and found that Mark is quite a homebrewer.  He wrote a nice series of articles for 73 magazine in the early 80's.   Here they are:

http://mikeyancey.com/73mag/listauthor.php?Author=WA0RBR


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

Sunday, April 28, 2013

Direct Digital Synthesis

I just bought one of these.   I hope to hook it up to an Arduino and turn it into a VFO.  Or a signal generator.  Six bucks!

http://www.amazon.com/dp/B009I7DR7E/ref=pe_175190_21431760_3p_M3T1_ST1_dp_1


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

Friday, April 26, 2013

A simpler DC motor



A few years ago Alan, VK2ZAY, showed Billy and me how to make a very simple DC motor.  This one looks even simpler.  I'm guessing that the bottom of the coil is making intermittent contact, setting up flux lines that get torqued by the magnets' field.  

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