These are HF ham radio transmitter/recievers that connect to a computer over USB, and allow communication on digital modes on what we call low frequencies these days (but they're also called Shortwave even though they're now the longest waves we use). Technically one is supposed to have a ham radio license to transmit on these frequencies, although anyone is allowed to listen in.
This is the kit they were building:
We used the video microscope and all six soldering stations! It was the most soldering happening at the same time in sudoroom in a long time. The event will happen again on Wednesday.
