Patience, as the old saying goes, is a virtue. However, after listening to my friends rave about he BITX40, I couldn’t bear to wait three or four weeks to get my hands on one. So, I paid the
extra $10 for shipping and was delighted when just four
days after I’d placed my order, the BITX40 arrived at my
door. (Note: Shipping is free, but for buyers in the US
there is a long wait time for delivery.)
The BITX40 comes as a kit, but it’s not a kit like most
of the ones I’m used to getting for under $100. For one
thing, the main board comes completely built and tested.
All the builder needs to do is add the peripheral
components along with the connecting wires.
The mic, the volume control, the power connector,
the antenna connector, and the digital VFO all need to be
connected by the builder; most of these connections
involve some soldering. Building the BITX40 was not too
difficult, mostly because the instructions are so well
I took my time, double-checked all my connections,
and made sure to tin all the leads. I was done in about
two hours. Once I’d finished, my BITX40 worked the first
time I used it. In fact, it worked very well.
My first contact was with a station over 500 miles
from my own location. Not bad at all for seven watts! I
love that feeling of accomplishment which comes after
making a contact with a rig I’ve built myself. True, some of
the BITX40 is prebuilt, but there’s plenty left for the
If you’re thinking of buying the BITX40, take note that
it does not come with an enclosure or a speaker. Both of
these items must be supplied by the builder. The
remainder of the parts (including the Raduino [Arduino
Nano microcomputer]) are included in the kit.
The genesis for the BITX40 grew out of Farhan’s
desire to one day bring amateur radio to people in low
income countries around the world. He wrote his original
design in 2003 while on a long flight from Stockholm to
India. Upon his arrival in India, he built a 20 meter
transceiver — the first BITX20 — in only three days.
Farhan’s goal was to offer a design for a simple
transceiver which could be built from inexpensive
components. Farhan likes to tell the story of how he had
to use ordinary washers instead of much more expensive
toroids. There was no kit back then, and no plan to offer
one. The builder was expected to obtain the necessary
components and then build their radios from Farhan’s
The BITX20 generated a little interest, but Farhan
realized that a significant number of builders didn’t have
the adequate training nor the necessary test equipment to
complete their rigs. Elmers are few and far between, and
radio clubs — which in the early days, often provided test
equipment — aren’t as available as they once were.
Farhan realized that there was a definite need for a
transceiver kit that would not only introduce the radio
amateur to the joy of building their own rigs, but one that
would not require any specialized skill or equipment. So,
Farhan built and tested the main board, changed the band
from 20 meters to 40, and with his small business
gathering steam, the BITX40 was born.
Building the BITX40
Assembly instructions for the BITX40 can be found on
If you spend any time around ham radio's low power enthusiasts — better
known as QRP operators — the chances are it won't be long until you hear
one of them mention the BITX40. Designed and built by Ashhar Farhan
VU2ESE of India and priced at a very competitive $59, the BITX40 is a
single side-band transceiver which puts out between seven and 10 watts of
power. With news of this hot new rig spreading mostly by word of mouth, the
BITX40 has suddenly become the talk of the QRP world.
November 2017 37
Main board for the BITX40.