The mcHF QRP transceiver. It is a small, home-brewed amateur radio project. Firmware is released as open source and most project files are released as well, with the only restriction of not commercial use (manufacturing and sales of kits or complete product).Looking at the block diagram (Fig1) it should be clear that my design goal was to make it as cheap as possible – without sacrificing functionality – and include the ability to add new features via simple software update.

Features

Standalone and compact embedded transceiver
Continues RX coverage 2-30 Mhz
5W output power
CW, SSB, AM and FM – transmit and receive
300/500 Hz CW and 1.8/2.3 kHz SSB filters with adjustable passband centering
3.6 kHz “wide” filter plus 5, 6, 7.5 or 10 kHz “extra wide” filters for SSB/AM reception
SSB/AM Transmit Speech processor
DSP noise reduction
DSP automatic notch filter
Spectrum scope
Waterfall Display
Highly configurable with a wide variety of menu items

mcHF Kit

It took some two years to the moment i can offer the mcHF in kit form. It consists of two boards with populated SMD parts and extra components supplied in plastic bags. The kit does not include speaker, final MOSFETs and enclosure.

It is worth pointing out that the kit requires some advanced soldering skills and knowledge in electronics as mods might be required. Also extensive tuning and calibration might be needed, or sometimes debugging of problems. It is not recommended as first kit or if you expect to be on the air after few M3 bolts tightening.

About

“Hello.

My name is Chris and my amateur radio callsign is M0NKA. I dedicate this website to my homebrew mcHF project.

The original idea was born few years ago when I got really interested in the 70Mhz band and found out that I had to homebrew something as commercial gear at that time was not available. My choice was Softrock Ensemble and OZ2M transverter. The extra part was a bulky and power hungry PC. So I decided to replace it with an ARM microcontroller. This is how the TRX4M project was born and I have been on the air with it ever since.

Last year I decided to remove all extra complexities from TRX4M and produce a design for a very cheap, affordable and functional QRP radio. This is the mcHF.

My major inspiration was the Softrock and the SDRCube projects. Without those I wouldn’t have had an idea where to even start. I also love the KX3 form factor and the ICOM IC-7600 user interface, you can see some design ideas from both have inspired the mcHF look. My gratitude also to Eric Brombaugh for sharing his I2S driver source as it gave me the push to pursue this project on the STM32F4.

Also special thanks for continuous help and encouragement from Brian (G0MJI) – the first ever mcHF Beta tester. And my good, old school, buddy – Nikolai (LZ2SEX) with his valuable analogue electronics experience and ideas.

Greatest thanks off course goes to Clint (KA7OEI) who took over the mcHF source code in the last one year and I can say that the mcHF is now a complete radio transceiver.

You can post comment on any of the pages, keep in mind it takes time for approval due to large amount of automated spam posted by bots. Or you can contact me via e-mail(djchrismarc at gmail) or page me on twitter @M0NKA_.

And now, thanks to the great effort of Andy (G6LBQ), the mcHF project has its own Yahoo support group. You can sign here.”