Adding a fan to keep an older mobile transceiver cool is easy to do with ready made parts.
I had an unexpected source of RFI which took out my internet from Verizon FiOS. The fix was simple, but the process to find it was a bit tricky.
WSPR is an interesting mode and offers some unexpected spotter locations. With as little as 200 milliwatts of power, you can reach half way across the globe.
There may be some dependencies on the grid needed to use your favourite radio communication mode(s).
I have never had an outdoor HF antenna until now, and what a difference with the same antenna outdoors versus indoors. I managed to hang an OCFD antenna for 40, 20, 10 and 6 meters in a very small crowded lot.
You do not need a DMR radio to get into a DMR network such as BrandMeister or TGIF. You can use C4FM, D-STAR, and others with some simple configuration on Pi-Star.
I upgraded the Kenwood SP-230 speaker using the Phits K95A and Phits GPH-X80 kits. The new speaker and foam made quite an improvement in detail and sound quality over the original speaker.
I found a deal on a Kenwood MC-50 Desk Mic for my TS-530SP or TS-830S. All that was needed was a new 4-pin connector and the mic worked perfectly.
I was able to solve an issue connecting a TRS-80 Model 100 to a Kantronics KPC-3 TNC.