One Knob Wonder

[VK6YR]

I was intrigued by Peter Parker VK3YE's "Knobless Wonder" transceiver design (AR April 2014) and after subduing the initial urge to melt solder, I had a lurk around the web to see what others had done with this interesting project. One article that caught my attention was a modified design by Frank VK6FH http://www.vk6fh.com/vk6fh/7mhz_xcvr.htm
and I decided to go with this. As I progressed with the build I added a few mods of my own. Firstly, an Rx pre-amp, and then a RF gain/Volume control (hence 1KW) as it offered control over strong overloading signals. Early in the construction, I added another relay to separate the microphone amp from the audio amp to quell a feedback squeal when the PTT was released. I used an MTP3055VL in the PA to put out approx. 4 Watts at 7.160MHz.
As one who has in the past spent countless hours making lovely PCB's only to have them spoilt with a necessary circuit change, I opted for "Ugly" style construction on a sheet of PCB for this project. I make no apologies for the less than pretty result as in my experience, a one off project of this kind almost always requires changes and mods during or after the build. I found this to be a great project and the few little problems along the way were fairly easily solved. My thanks to Peter VK3YE and Frank VK6FH and apologies for my intrusions to their designs.
Geoff VK6YR.

https://www.youtube.com/watch?v=poJNoBrDko0

[VK3YE]

Thanks Geoff - glad you enjoyed it.

These videos demonstrate reception of Geoff's rig 2400km away in a noisy suburban location (others in quieter areas
got better signals - as strong as 5/7 elsewhere in VK3).





Another article about this rig is in this month's AR magazine. A printed circuit board is available from VK2EVB.

With no controls the user has no choice but to accept what this rig throws at them - frequency, volume, rf gain etc.