Friday, August 24, 2018

2018 ~ The Year of SSB Transceivers

FT8 & WSPR on your Homebrew Rig!

For several months now I have been working on a new SSB rig that will be the subject of a couple of articles in  future issues of the GQRP Club publication SPRAT Magazine.

Run don't walk if you are not already a member of the GQRP Club so by joining you can gain access to the articles. Most of my operation is on SSB but I have come to recognize that many in our ham community have moved over to the digital communications dark side and therefore challenged myself to enable my SSB rig design to "do digital". I am happy to report that I have been successful in running both WSPR and FT8 from the new rig.

All that was needed was the software WSJT-X, a $10 (delivered) sound card interface board, some cables and an old computer with a serial port DB9 connector. That is it. 

With technology advancement comes change. Most new computers do not come with a serial port and thus that presents some difficulties in using the sound card interface device. A tour of Adafruit Industries webpage revealed a product that provides a USB to Serial interface device that has as outputs the DTR or RTS signals (either one) that will key the transmitter. It is a modest price ($15); but opens the door for possible uses with a Raspberry Pi3B or an Asus Tinker Board. WSJT-X  comes in Windows and Linux distributions so there may be a possibility for a very small (and portable) FT8 station. I have ordered one of the units and you can read about it here

Here is the interface board kit.

But the real proof is how it works on the air. Below are some screen shots that document the contacts I had. In the WSPR log you will see an entry from VK2ALR when I was spotted 7500 miles away running 5 watts on 40 Meters.

But the most Buzz today is about FT8. So I had to try my hand at that mode and so far have made two contacts. Here is a log of the 2nd contact made this afternoon.

Now I must confess that the FT8 is almost like remote sex. Push a button and the computer takes over and makes the contact. So no long rag chews here. But FT8 levels the playing field using low power and modest antennas.

I am in the process of reworking the sketch for the VFO (it has two). One VFO will boot up normal at 7.2 MHz and the second one I will program to boot up on 7.074 MHz. Thus, flip the VFO select switch and flip the rig to USB and you are on digital!

This is exciting.

Pete N6QW


  1. Mama mia! OMG! WTF? N6QW on WSPR and FT-8? We are truly approaching the apocalypse.

    1. Shortly it will be revealed the real WHY. These two modes are very useful for checking your antenna and its directivity. A real bonus,


  2. Pete (and Bill)

    I finally broke down and joined the GQRP Club. I totally blame you guys, you made me do it.
    I needed that "Sprat" magazine fix. For that thrill to see you guys on the cover!

    I even had to deal in foreign currency for the first time since the mid-90's when I had a work related trip to Bromont, Canada. At least in Canada it was still called dollars and cents, you just paid a lot more of them for things. plus VAT

    (btw my Paypal membership transaction didn't go thru with payment by bank method, I had to switch the paypal payment method to payment by credit card.)

    First it was "The Construction Club" with it's "Hot Iron" magazine but lo that just just the thin end of the wedge. Then the free issue of QRP ARCI's "QRP Quarterly" was download. I was sorely tempted but I stood firm and didn't join. Now we come to this foreign QRP club and it's "Sprat" magazine.

    What's next guys? Am I doomed to fruitlessly search boxes under tables at hamfests, scouring online auction sites, delve into dusty used bookstores to find one last remaining high-lighted, dirty, torn, tattered and dog-eared copy of "Experimental Methods in RF Design" only to succumb to the dark side and go down and dirty to a late night deal on a pirated copy from a car in the back parking lot of a FedEx Kinko's?

    1. Raplh,

      It is also a sinister and deliberate plot to have you "amp up" the depletion of your bank account, Sounds like it is working.



  3. This is what you get when Pete has too much time on his hands because he stopped posting the detailed builds.
    He will make excuses about SDR and digital modes being beneficial, but we all know that WSPR is a 'gate way mode'. And now he is mainlining of FT-8! This is getting serious.
    Bill, we may need to do an intervention!

    1. Hi Jim,

      Hang in there in time all will be revealed. There is a reason why WSPR/FT8 is being pursued and it is a complement to a project that will soon hit the streets.

      Thanks for your post. No need for an intervention.

      Pete N6QW


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