In December 2016, Ashhar Farhan and the company HF Signals in India released the BITX40, a simple SSB radio for 40 meter HF. For $45, one could buy the kit with its preassembled board and minimal soldering required to be on the air. Soon after, it was packaged with an Arduino/si5351 based digital tuning mechanism called the Raduino. A digitally tuned HF radio, even as a kit, was only $59!
Up until recently, you could still buy a BITX40. But HF Signals has decided instead to focus on the BITX40’s, the uBITX. We’ve not covered the uBITX here for various reasons, but it’s a multi-band dual conversion SuperHet that has its roots in the original BITX20/40 design. Wait, BITX20?
BITX Roots: Homebrew Radio
That’s right, the BITX40 was not the original BITX. In the early 2000’s, work being done in the homebrew community, along with work by Farhan himself, culminated in the BITX20- a QRP 20 meter radio putting out 5 watts of power. It featured Bidirectional amplification stages, which greatly simplified the topology of the radio and therefore its construction. It was a homebrew hit, and many were built from schematics. Interestingly, the first group buy of parts was arranged by none other than Hans Summers, who now runs QRP Labs.
It wasn’t until 2016 that the BITX40 was made available as a pre-built kit. the BITX20 design was optimized for small scale mass production, and the BITX40 was born. So, what happened? Why is the BITX40 dead? Are there other options? Read on to find out.
The End of The BITX40
In the last week of October 2019, Farhan announced the end of the BITX40 as sold by HF Signals. He posted in the BITX20 group at Groups.io. Here’s an excerpt of what he said:
