Last week I ordered a Stellar WSPR RK-1 Receiver Kit for the 30 meter band.
I received the kit today and built it after dinner in a little over an hour. There are about 40 through-hole parts to install on a board with plenty of real estate. Anyone who’s built a QRP kit will find this kit very easy to assemble.
The two necessary cables are included – a USB cable for DC power and an audio cable to feed received audio to the computer’s sound card. Alignment consists of transmitting a weak signal on the proper freq (with your main station rig or a sig gen) and then tweaking a small cap to put the received signal in the proper place on Spectrum Lab.
Once this was done, I started WSPR 2.0 and configured my laptop’s sound card to receive audio on the “Mic In” jack. Soon after, the first spots started showing up.
The antenna jack for this kit is simply a 2-pin terminal board and I’ll be replacing it with a BNC soon. With an alligator clip jumper I’m connecting the board’s antenna terminal to the center lead of the coax going up to my dipole so the connection for now is far from ideal.
Instructions that come with the kit reference the websites for downloading Spectrum Lab and the WSPR program.
It is a simple to build and align kit – almost perfect for its intended users. The manual could be more detailed – there’s a good amount of room for improvement in that department. While building the kit and going through the alignment, I noted several areas where non-hams could become confused.
The kit is not aimed at hams and certainly won’t compete with a dedicated ham rig at digging out WSPR signals – it is designed to be a part of school curriculum and I hope George WB9LVI is selling them by the score and increasing awareness of ham radio at schools. It provides students a way to participate in propagation studies and ham radio without needing a license to do so and that will be the eventual function of my receiver.
I think it would also make a great kit from a ham to an interested friend or family member – or as a father-son project.