When VU2ESE introduced the BITX40 “semi-kit” in 2016 it was an immediate hit. No one could imagine a SSB transceiver for $49. Then in 2017 he started selling it with a digital frequency synthesizer and display for $59 and sold thousands. Little wonder! In December,2017 his company started shipping the μBITX (or micro BITX) a fully wide-band 3 to 30 MHz transceiver with upper and lower sideband and CW, power up to 10 watts and solid digital control. The wired and tested circuit boards and all the parts, plugs and cables are shipped for only $129. All you need to do is put it in the enclosure of your choice.
Unlike the single conversion superhet BITX of the past, the μBITX is a dual conversion with superior amplifiers and a 8 pole crystal filter. A 45 MHz roofing filter and the three fully programmable synthesized oscillator frequencies make for exceptional stability and very few spurious signals.
The main circuit board is only 5 1/2” deep and 6” wide. With the control and display module is plugged in the height is still less than 3” high. It runs from 12 volts DC and pulls about 1.5 amps on transmit peaks, about 190 milliamps on receive. Great for portable use. The backlit liquid crystal display is about 3/4” high and 2 1/2’” wide providing an easily read 2 lines of 16 characters each. Easily read in full sunlight. No squinting.
The RF output amplifier uses a pair of hefty (and cheap!) power field effect transistors in push-pull. If you manage to accidentally destroy them, replacements cost under a dollar. The transceiver is built with mostly quite large surface mount components with an uncrowded layout that generally follows the schematic layout and has clearly marked silk-screened labels for most all parts.
The simple design and straightforward layout makes modification quite attractive and easy. Like the BITX40, you can add whatever features that you can dream up. Customize it to suit your needs. It is cheap enough to keep you from worrying about destroying an expensive piece of equipment. Things that you would never consider attempting is now an inviting possibility.
Like most of the expensive transceivers from Yaesu, Icom, and Kenwood, the μBITX uses a digital micro controller for tuning and general operation. Unlike those other radios, however, this micro controller is a basic Arduino® Nano. Replacements available from many sources less than $5 USD! The use of this device means that the user has full and easy access to all features! Free programming tools, free operating system, and free access to a range of modifications and features available by instant download from scores of μBITX programmers.
This flexibility is probably the most exciting thing about the μBITX (aside from the price!). The user can customize operation of this equipment to work exactly as he wants. Imagine a new feature? Program it yourself! The actual loading of the new program into the radio takes mere seconds and is accomplished with just a USB cable to your computer. No other hardware needed.
There are several sources of different style cabinets for the μBITX but many choose to “upcycle” cases from other equipment found in the junk box or thrift stores. Metal ammo cases make sturdy weather-resistant emcomm enclosures. Most of the enclosures that ND6T uses were former data switch units, found at swap meets and second-hand thrift stores. These are sturdy metal cases, easily drilled with simple hand tools.
Simple, elegant, easily customizable. The μBITX is a great choice for portable, emergency communications, or just plain fun. Check it out at http://www.hfsignals.com
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