Monday, June 03, 2013

Knobless Wonder 40m SSB QRP circuit from VK3YE

Peter, VK3YE, recently showed me a new home brew fixed frequency single sideband rig he dubbed the "knobless wonder". I think this is a great group project where the fact that it's fixed frequency is an advantage in encouraging contacts between builders.

He's given permission for the circuit to be published here (click to enlarge).

I highly recommend Peter's walkthrough video complete with a series of contacts on the actual rig.

Thanks Peter!


  1. Dave B.5:56 AM

    Thanks for sharing this. I've got a friend who's interested in homebrewing, and we might enjoy a project like this.

  2. This is a very neat design and I am inspired to construct it. I have one question, though. It appears that the pin numbers on the LM386 are incorrect, specifically pins 1 and 2 appear to be swapped. Am I correct or is this just the different way the pins are being used on the LM386?


    Mac / AE5PH

  3. Mac, you might be right about the LM386, I haven't heard a peep out of the receiver. I've been concentrating on getting the transmitter side going so far.

  4. This is SSB transceiver ? but no BFO on schematic , Why ?


  5. IMHO,
    This is the simplified BITX with relay.


  6. Is this direct conversion transmitter/receiver? so the OSC actually BFO ?

  7. Yes the oscillator is the direct conversion bfo

  8. Hello friend Peter Marks.
    Very good your blog, congratulations. I liked your knobless the project, it is quite simple, it is a version equal to a DSB with the filter crystals ladder without VFO, very good your project idea. I would like to ask permission from the Lord for me to draw it and post on my blog, because it is simple and easy to assemble interests beginners in home assembly accompanying my blog. Friend I am available by e-mail.ou blog:
    Thank you.

  9. Peter, user Bf 494,Bf245,Bf 892,Bc 549,ok.