Pebble HF: a low-cost portable QRP radio kit, first look

I'm not sure if I saw it first on the Ham Radio Duo YouTube channel, another ham radio YouTube channel, or on the Pebble HF website, but I came across the Pebble HF radio kit, a $ 50-ish dollar kit that allows you to play around with a low-cost radio that is fun and easy to build and cheap enough to experiment. What exactly is the Pebble HF? Well its a QRP ~5w 20M monoband radio but it is also a project. As the website says:

Pebble HF is an open-source design based on the classic uSDX. Hardware design by Barb WB2CBA and firmware by Guido PE1NNZ, modified by Mike N4FFF.

I had to sign up for an email waitlist, and I must have gotten in line pretty quickly because I was able to place my order pretty soon after I signed up, and once my order was placed, I received it in the mail very quickly. Once it arrived, I got the kit built extremely quickly. I like simple kits, and I have been looking for some projects to offer the joy of soldering and building but without needing to be extremely complicated.

I love this project's idea and every chance I get I support community and open source projects.

Building the Kit

The Kit arrived very quickly and was extremely simple. The listing said it consisted of only fourteen through-hole components (fifteen if you add in the optional ICSP header for later firmware updates). The most complicated thing was winding two coils, one with windings and one with nine (some of the original videos said ten, but this has been changed in the manual and mentioned in several places)

The kit was extremely easy to solder and took me about an hour and a half. Most of this was watching the video the first time (I thought the kit would take longer to arrive and hadn't watched/read the build info before it arrived). For someone who had a clean setup and minimal soldering knowledge, the build could be accomplished in closer to 30 or 45 minutes.

I have been very impressed so far; there is essentially nothing on the board that wasn't marked clearly enough to 

First Thoughts

I have yet to test the radio besides attempting to receive signals. I was able to hear a little, but my testing setup and location aren't very good. I don't expect much, but what I have been able to get so far is pretty amazing, especially out of a $50 radio. The only thing I don't love is that the kit didn't come with a barrel plug to power the radio from something other than USB-C. I had an extra cable, but if I didn't, I would have had to order something, and this would have added a ton of time to the project waiting for parts to arrive.

I'm going to update this post once I have a chance to take this radio out somewhere quiet to give it the best chance. If I am able to make an SSB contact, I will definitely push to do a build for the club once they become more available. I am also going to use this as a reason to learn CW.

Things I am going to do with this radio in the future:

1. Field test- try to make actual contacts
2. Test digital modes (FT8) using a cheap USB audio sound card.
3. Build a mini-mic (I plan on getting a QMX at some point, so I'll get something that works in it too).
4. Make an SSB contact.
5. Make a CW contact on this radio.

I'll update this as we go.