uBITX V6
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| Frequency | RX/TX: 3-30 MHz general coverage (all HF amateur bands 80m-10m) |
| Bands | 80m-10m (general coverage 3-30 MHz) |
| TX power | 10 W (More than 10W on 80/40m, ~7W on 15m, ~2W on 10m (stock IRF510 finals); power tapers steeply with frequency. SSB/CW only.) |
| Modes | SSB (USB/LSB; auto-selects proper sideband, user overridable), CW (with semi break-in keyer) |
| Weight | 300 g (10.6 oz) - ~300g bare board assembly. Assembled in full kit metal case: heavier (not specified by manufacturer). |
| Connector | BNC (on full kit metal case) |
| Year | 2017 |
| antenna | BNC (user-installed on case) |
| mic | electret microphone included (wired to board) |
| key | 3.5mm or user-wired (CW keyer input on board) |
| phones spkr | speaker/headphone output (speaker included in full kit) |
| dc in | 2.1×5.5mm barrel jack (12-14V DC) |
| usb | USB mini (on Raduino, for firmware updates and Arduino programming) |
| power req | 12-14V DC. Current varies by TX power level. Low current draw on RX, suitable for battery operation. |
Estimated (unverified): Board revisions: V3 (first production, Dec 2017), V4, V5 (Feb 2019, second IF moved to 11.059 MHz), V6 (Dec 2019, current, color TFT). RX is operationally ~3-30 MHz; the upconversion scheme has a ~500 kHz architectural floor not tuned in stock firmware. Pricing (~$160 basic / ~$209 full kit) shifts over time.
A complete all-band HF SSB/CW transceiver kit for $209 shipped worldwide, with 10 W on the lower bands. A double-conversion superhet with a 45 MHz roofing filter and an 8-crystal SSB filter gives clean receive, and the Si5351 oscillator is stable. The V6's TFT color display is a clear upgrade from the original LCD. All SMDs are pre-populated, so the user only wires connectors and mounts the board. Active community firmware adds CAT control, Nextion display support, WSPR, and many other features. It is open-source throughout and has helped put many new operators on HF, especially where commercial transceivers are expensive.
Power tapers steeply with frequency: over 10 W on 80/40 m but only ~2 W on 10 m with the stock IRF510 finals. The receiver has no AGC and no RF gain control, so strong nearby signals can overload it until you add a community circuit. Early boards (V3/V4) were known for spurious and harmonic output and benefit from filter mods; later boards improved this. No enclosure, microphone case, speaker, or power supply is included with the basic kit, and you wire up the connectors yourself.
An affordable all-band HF kit. Ashhar Farhan's uBITX made all-band HF accessible globally for about $200. The double-conversion architecture with an Si5351 and an 8-crystal filter gives workable performance, and the community firmware ecosystem turns it from a basic kit into a more capable platform. For first-time builders, developing-world operators, and anyone who wants to understand how a transceiver works from the inside out, it is a common starting point.
The uBITX answers a simple question: how cheaply can you build a real, all-band HF radio? The answer, from Ashhar Farhan and his company HF Signals in Hyderabad, India, turned out to be remarkably cheap. For around $160 the basic kit gives you SSB and CW transmit and receive across the entire 3-to-30 MHz range, every HF ham band from 80 through 10 meters, on a single pre-assembled and tested board. It descends from Farhan's earlier BITX designs, and like them it is deliberately simple, open, and made to be understood and modified rather than sealed shut.
It is a conventional radio, not an SDR, and that is part of its charm. A double-conversion superheterodyne with a 45 MHz first IF and an 11.059 MHz crystal-ladder filter, it uses an Si5351 clock chip for its oscillators, controlled by an Arduino Nano on a little daughterboard everyone calls the Raduino. Because the brains are an Arduino, the firmware is open and endlessly hackable; the KD8CEC community firmware is widely flashed in place of the stock code. The current version six ships with a 2.8-inch color TFT display where earlier boards used a two-line LCD.
The honest part of the spec sheet is the power. The IRF510 finals deliver more than ten watts on 80 and 40 meters but taper steeply with frequency, to around seven watts at 15 meters and only a couple of watts on 10. The receiver, likewise, is capable but plain: there is no AGC and no RF gain control, so a strong nearby signal can ride over everything until you add one of the many community circuits for it. The transmitter benefits from extra filtering too, the early boards in particular were known for spurious and harmonic output, which later revisions improved.
None of that is really a criticism, because the uBITX is sold as a starting point, not a finished appliance. You supply the enclosure, wire up the connectors, and then, if you like, spend years improving it. For a first homebrew HF rig, or a hackable second radio, it is hard to beat, and it sits naturally alongside other open, low-cost projects like the mcHF SDR or the single-board QRP Labs QCX. HF Signals has since moved upmarket with the Raspberry-Pi-based sBITX, but the little uBITX remains the one that put all-band HF within almost anyone's reach.