I too used to use those Radio Shack kits with the spring terminals, &amp; loved it! I wound up teaching myself so much that I was able to start in &#x27;Year 2&#x27; of a local vocational school for electronics repair- just from what I learned from those kits.<p>Later on, I felt limited by how they were designed, and found that &#x27;Free Radio Berkeley&#x27; sold kits to build pirate radio stations, which I thought was the coolest thing I&#x27;d ever found, so I ordered some kits from them to work on. It turned out that the kits were missing quite a few parts (which weren&#x27;t available through Radio Shack), so I had to search &amp; find mail-order electronics suppliers to order the missing parts from. Another thing that was &#x27;wrong&#x27; with these kits, which I had to find a solution for, was that they only included pictorial schematics- no use of standard electronic schematics like you&#x27;d find everywhere else. So I had to draw my own schematics based on what was present on the circuit boards. This eventually helped me in the long run, as I was able to bring the transmitter + the schematics I drew up to job interviews, &amp; I landed my first electronics repair job based on my work on the transmitter.<p>EDIT:
Another thing you might look into that I found educational&#x2F;fun is mods for CB radios. A good CB shop can sell you a CB Radio &amp; parts which allow you to make some changes &amp; add extra functions by making simple alterations to the circuit boards. I added more wattage, a frequency slider, extra channels above &amp; below the standard 40, &amp; sideband to a Cobra 148GTL back in the day. There was a small community of people on the radio where I grew up, &amp; I would stay up late at night talking with them on my fancy radio. Later I got a linear amplifier, but was always afraid to use it since they&#x27;re illegal- so I got rid of that to play it safe.