The qcx+ comes from http://qrp-labs.com/. It’s the kit I mentioned on the Roundtable a couple times, and I finally bought and built it. The manual has a very nice circuit description write up. It’s a good value at $55 radio + $25 aluminum case + $20 shipping.
It’s a fun little rig and is unusual for a qrp one. In the receive chain, it goes straight from the bandpass filter at the antenna to i/q detectors, sdr style. And the transmit chain uses a Class E amp, which is not very common. The microprocessor provides alignment tools and a keyer for straight key, iambic A, iambic B, and ultimatic. I use a Four State QRP Group tuner because I’m not sure that it can handle high swr. (The 4 state tuner never presents more than 2:1 vswr to the rig.)
I finished it Sunday night, and Monday evening 40m was dead when I tried. Happily, Tuesday after work I called cq 3 or 4 times and an op came back from Ontario, just outside Toronto. He gave me a 559, which I was happy to hear. I measured output and with my 13.8V supply, it puts out a scorching…4.2W 🙂
Here are some pictures for you…