My Eleven Contacts using the SolderSmoke Direct Conversion Receiver -- It is NOT a toy!

I have made 11 contacts using the SolderSmoke Direct Conversion receiver.  Ten of the 11 were after June 3, 2025. This was in very casual operation, operating with less than 1 watt with a dipole antenna.

Alan W4AMV

1. The first of course was back in February 2023 with W4AMV.   On this one I was using a simple "10 Minute Transmitter" that I threw together thinking that I would use it to demonstrate the receiver to our high school students.  "Wait a minute," I thought.  I called CQ and W4AMV answered.  I was running about 100 mW. He too was using homebrew gear.  https://soldersmoke.blogspot.com/2023/02/first-qso-with-high-school-receiver-100.html

2, 3, 4.  On June 4, 2025 I again fired up the 10 minute transmitter.  My T/R scheme was VERY simple: I have an MFJ coax switch that I use to select the rigs that will connect to my various antennas.  On the antenna switch I selected my 40 meter dipole.  I ran two pieces of coax from two different positions on the MFJ switch.  One I marked RX, the other TX.  The transmitter and the receiver were working off 9 volt batteries. I quickly worked N2WJW. Gil in New Jersey.  But I noticed that the 10 Minute rig was drifting.  So I pulled out my trusty old Tuna Tin 2 transmitter and used it to heartlessly replace the 10 Minute Transmitter.  Now with SEVERAL HUNDRED milliwatts, I worked W2XS, John in New York on June 5, 2025.  Later that same day I worked N9FGC in Indiana.

 

K1OA's Rig

5. My most amazing contact came on June 7, 2025. Here is my log entry: 40CW K1OA First 2 way contact with station also using a SolderSmoke DC Receiver!At around 0630 EDT on June 7, 2025 I heard K1OA calling CQ on 7030 kHz CW. This was exactly where I had a crystal.  I called him, but he didn't hear me.  I sent him an e-mail.  We tried again -- he heard me calling him and I heard him responding by calling me, but I don't think we succeeded in exchanging signal reports. It was close, but no cigar.  I had to walk the dog. Scott and I agreed to meet on 7030 kHz at 0730 EDT.  Arggh.  There was a QSO there.  I thought we might have to try to change frequency, but this would have been tough because both of us were crystal controlled on transmit.   Fortunately, the contact on 7030 kHz wrapped up.   Scott called me, I responded, and we were able to exchange signal reports.  I was so excited that I almost forgot to hit the record button on my phone.   But I caught the last minute or so.This was really something.  This really goes to prove what Dean and I have been saying all along:  this receiver is not a toy!  It can be used for real ham radio contacts.  And now we have had these receivers on both ends of a contact.  For transmit, Scott was using a KA4KXX transmitter with about 3 watts output.  I was on my Tuna Tin 2 at about half a watt output.

Jim W1PID

6, 7, 8.  Later on June 7, 2025 I worked an old friend, Jim W1PID.  Jim is a friend of Homebrew Hero Mike AA1TJ, and was involved in Mike's effort to cross the Atlantic with a voice-powered rig.  Jim also was one of my contacts with the ET-2 QRPppp rig. I also worked WZ2J  Vin in NJ. I also worked John W2XS again. 

Mike WB8VGE

9.   June 11, 2025  (Really evening of 10 June 2025) Famous homebrewer, Anchorologist, Heatkit authority and fellow member of the QRP Hall of Fame Mike Bryce called me!  40CW 0034 WB8VGE Mike Bryce came back to my CQ! Mike wrote: Nothing like quartz locked frequency control!You know it sounded pretty damn good at 500mW. You were holding your own until QSB would take you out in a deep fade. But all in all, one hell of great QRP QSO.I was running my Ten Tec Scout that I had just put back together a couple of days ago.  Got around to putting the case back on it tonight, and had it cooking in the back ground just listening to the stations come and go. I had worked a few POTA stations near by and found a quite spot. I was working on a project when I heard your CQ through the din of the 40M band. Glad I took a break and worked your QRPp signalbest 73  QRP # 4816 You get a QSL for that QSO!

Here's my post about Mike, WB8VGE:  https://soldersmoke.blogspot.com/2018/09/wb8vge-on-qso-today-qrp-hb-boatanchors.html

10. Around June 11, 2025 I worked W4MY in a contest. 

11.   On June 12, 2925 I worked some DX with the rig.  It was VA3ICC, Ian in Ontario. 

Ian VA3ICC

All of this reinforces something that Dean KK4DAS and I have been saying all through this build process:  this little DC receiver is not a toy.  It can be used as a serious ham radio receiver and it can -- even when paired up with a very low-power crystal-controlled transmitter and a simple antenna -- make some great ham radio contacts. 

SPRAT, the FETer, DLR headphones, and recent QSOs on the ET-2

Yesterday we had QSO #13 on the ET-2.  This was with Jim W1PID.  In an earlier contact Jim told me I had some chirp.  I fiddled with the coupling cap and the bias pot and am now T9!  These days, chirp is an endearing, nostalgic problem to have.  Thanks for the report and QSOs Jim! 

Contact #9 was with Fred K9SO.  He is in Wisconsin and QRZ.com put our distance at 633 miles.  That is our DX record so far.  Not bad for 92 milliwatts to a dipole on 40 meters. 

Most of my contacts come as a result of pleas for assistance on DX Summit or the SKCC Sked page.   But I did make one "random" contact: Contact #6 with N2VGA.  He just heard my CQ and gave me a call.  FB. 

I checked to see if OM Glen Yingling W2UW -- the guy who started all this with his ET-1 -- is still around.  He became a silent key in 2012.  But his ideas live on... 

SPRAT 137 (Winter 2008/09) has a great article by QRP hero G3XBM.  Roger built a version of the ET-1.  His was for 80 meters and he called it the FETer.   FB.   I was struck by his estimate of the sensitivity of the ET-1 receiver: -100 dbm.   I measured the N0WVA receiver (the one that I am using) has having a minimum discernible signal of -93 dbm.  Pretty close.  We may be at the limit of what you can expect from a single transistor receiver. 

SPRAT 137 had something else that really resonated with me.  G3YVF had an article on a minimalist rig using only one 6V6 tube.  Geoff opened the article with this warning "Don't try this unless you have a set of balanced armature type DLR 'phones as they are really sensitive."  I have a collection of old headphones that I picked up at hamfests in London years ago.  When building the ET-2, I checked all the old phones for sensitivity.  A set marked DLR was the most sensitive.  So Geoff's observation had been independently confirmed.   QRP Quarterly had an article comparing the sensitivities of old headphones -- we should dig that article up.   

SPRAT #137 is a reminder of what a great resource SPRAT -- The Journal of the GQRP Club -- really is.  As we say on SolderSmoke, if you are not a SPRAT subscriber you are just wrong!  Here is how to join GQRP and subscribe to SPRAT: http://www.gqrp.com/join.htm

QSO #3 with the ET-2 Minimalist Transceiver

 

The Radio Gods were clearly supporting me on 16 October 2019.  I had sent out a plea for people to listen for the 80 mW CQ from my ET-2 rig.   I had specified 0930 Eastern as the time.  Little did I know that there would be a contest at that hour (on a Wednesday morning!) on 40 meter CW.  There was no chance of my signals getting through.  I leaned that the contest would be over at 1000 hours, so I waited and called CQ again at that hour.  Jim W1PID had guessed that I would do that.  I immediately recognized his call -- he was often at the other end of Michael Rainey's most daring low-power adventures.  He was a participant in the famous Rexpeditions, including a coastal effort to send Michael's voice-powered CW signal across the Atlantic.  His normal operating habitat is in the field.  We had a wonderful QSO.  He told me I peaked at S-6.  

I have worked W1PID on at least two Straight Key Nights and this blog has had many postings about his long-standing involvement in QRP. 

Thanks a lot Jim!