BitX40
After reading reviews and watching many youtube video’s on the BitX40 SSB transceiver kit,
I determined to order one for myself as a Christmas present from my wife. I was pleased and very surprised with how quickly it arrived all the way from India.
It was well packaged in a nice plastic box and wrapped in cardboard packaging.
All parts were present and of excellent quality, these comprising of:4 & 1/2 inches by 5 inches SSB transceiver module, Fully tested for the 7 MHz band
The Raduino board with Si5351, Arduino Nano. Fully tested
High quality BNC connector for the antenna
Small electret microphone
Two earphone style audio jacks for the mic and the earphones/speaker
A set of DC power socket and plug
Volume control with on/off switch
10k linear pot for tuning
8 Brass standoffs with mounting nuts and bolts
Connectors with wires for all connections on the board
My first decision was to decide on what box I was going to build it into. Looking around my workshop I found just the right box for size and construction, however the front and back plates were full of holes from the equipment that was in there before, these would need replacing.
I had some nice scrap pieces of smoked perspex and some very thick gage aluminium. I thought the Perspex would make a nice modern looking front panel and the aluminium plate would serve as a back plate and heat sink for the PA transistor.
When trying to slide the panels into the slots of the two halfs of the plastic case it became necessary to chamfer the edges to a thickness that would fit the slots. For the front panel a secondary plate made from double sided copper PCB was placed behind the perspex to fit the DDS arduino and display, together with tuning pot, volume control and mic socket.
The microphone socket was replaced with a 8 pin type, as I had a spare Yaesu microphone I planned use.
Apart from the case, the only other bit of hardware required which was not included in the kit, was that of an 8 ohm speaker.
I was lucky to have a good collection of speakers of various sizes and impedances and so chose an oblong type, this being fitted to the right hand side of the case top.
When all the wiring was complete, I attached an antenna and switched on. A pleasing hiss came from the speaker with a faint background signal. On tuning around the band it was a surprise on just how sensitive the receiver was. I had no trouble resolving several european stations.
All good so far, but now it was time to connect a dummy load and power meter and see if I had some RF.
After connecting up the included electret microphone and push button switch into a small plastic case, the assembled microphone was plugged in along with a power meter and dummy load.
Speaking “HAAAALOOO” into the microphone produced a satisfying flick on the power meter. I had some RF without any smoke, success!
Using the Yaesu microphone produced a very low power level and so if I use it as I originally intend, some addition amplification after the mic will be needed. This I hope to do in the future along with fitting an S meter and the option for CW.
The whole point of the BITX project by HF Signals, founded by Ashhar Farhan VU2ESE, is for it to be Hackable, or quoting words from their home page -
“The BITX40 will inspire you to experiment". "Modify it, mount it, tweak it, change it”
I have enjoyed putting this rig together and look forward to modifying and experimenting with it in the near future. There is plenty of scope for modifications and additions to end up with an excellent piece of Ham gear.
BitX40 Kit source: http://www.hfsigs.com/
Arduino sketch: https://github.com/afarhan/bitx40/blob/master/raduino.ino
Later this year (November 2017), this project won for me, the TDRAC G4UNU Constructors cup for Kit built projects.
