QRP Labs QCX-mini
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| Frequency | single band: 160m, 80m, 60m, 40m, 30m, 20m, or 17m (select at purchase). Experimental 15m/12m/10m/6m (reduced power and sensitivity). |
| Bands | single band (select at purchase) |
| TX power | 5 W (~3-5W CW depending on band and supply voltage (about 5W on lower bands near the top of the voltage range). Optional 50W PA kit available.) |
| Modes | CW |
| Weight | 200 g (7.1 oz) - ~200 g assembled transceiver without enclosure. Optional aluminum enclosure: 95 x 63 x 25 mm. |
| Connector | BNC |
| Year | 2020 |
| key | 3.5mm stereo (iambic paddle) |
| earphone | 3.5mm stereo (earphone output — not speaker level) |
| ptt | 3.5mm stereo (PTT — for 50W PA kit or external amp) |
| cat | 3.5mm stereo (CAT control, 38400 baud TTL serial; also used for firmware update via a USB-to-serial adapter) |
| antenna | BNC |
| dc in | 2.1mm power barrel connector |
| power req | 7-14 VDC recommended. Receive: ~58 mA at 12V (backlight off). Transmit: ~300 mA key down at 12V. |
A full-featured single-band CW transceiver at pocket-money kit pricing (assembled costs about double). The built-in CW decoder works well even on weak signals. It has a WSPR beacon mode and built-in test equipment, so no external instruments are needed. The 58 mA receive current is very low for portable battery operation. The pre-soldered SMD makes the kit build manageable, the LCD is sunlight-readable, and self-alignment simplifies RF kit building. An optional 50 W PA is available for when 5 W is not enough.
Single band: you choose at purchase and are committed. CW only (unless you do the uSDX SDR mod). 5 W is QRP and may struggle on crowded bands. The kit needs careful soldering near SMD components. Five toroids must be wound (the input transformer is tricky). The class-E amplifier needs proper harmonic filtering to be clean. The LCD is small.
An inexpensive single-band CW transceiver kit (cheap as a kit, about double assembled) with a built-in decoder, WSPR beacon, and test equipment. It is a weekend kit build that puts you on the air with real performance, and one of QRP Labs' most accessible designs.
The QRP Labs QCX-mini is a single-band CW transceiver you build yourself, and for many operators it is the kit that first put them on the air with a radio they made. Designed by Hans Summers, it puts about 5 watts of Morse on one band you choose when ordering - 160, 80, 60, 40, 30, 20, or 17 meters - in a package the size of a deck of cards. It is not a digital or SSB radio; it is a focused, well-thought-out CW rig.
For the money the feature list is remarkable. There is a built-in CW decoder that reads incoming Morse on the little screen, a WSPR beacon mode, an iambic keyer with memories, and a clean 200 Hz receive filter. Most striking is the built-in test equipment: the radio contains its own voltmeter, RF power meter, frequency counter, and signal generator, so you can align and troubleshoot it without owning any test gear - which removes the biggest hurdle a first-time RF kit builder faces.
The build is approachable. All the fiddly surface-mount parts are pre-soldered at the factory; you install the through-hole components, of which the trickiest are a handful of toroids wound with enameled wire (the multi-winding input transformer is the one people fret over). It runs from 7 to about 14 volts, draws only ~58 mA on receive for long battery life, and connects through a 2.1 mm power jack, a BNC for the antenna, and 3.5 mm jacks for key, earphones, PTT, and serial CAT. Note there is no USB socket - it is built around an ATmega328P, and firmware updates go through the serial port with a USB adapter.
It comes as a famously cheap kit or, if you would rather not solder, an assembled unit for about double, with an optional aluminum case. When 5 watts is not enough, QRP Labs sells a companion 50 W amplifier. If you want digital modes instead of CW, the same company's QDX is the digital-only sibling, and the multimode QMX adds SSB and digital to CW. The original full-size QCX has been retired, but the mini and the larger QCX+ continue. As a first kit or a featherweight CW radio for the field, it is hard to beat.