Thomas Does Radio or Something

It was a great day out, we had gone scouting the park the day before, and I was on vacation to use up my remaining balance before my time resets next month. Wasn't quite above freezing, but my experience with Winter Field Day said that I had enough of a setup to definitely get on the air. It was off to Governor Nelson State Park ( wiki ), K-1452 in Waunakee, WI (Dane county) at EN53gd. I was hoping that there would be park staff to exchange our kiosk receipt for a real window sticker, but it was too late in the day when I got there, it seems. Easy enough to put the ticket on the dash and head to the parking nearest the lake. Wire for 20m on fiberglass pole set up in the dying light at Governor Nelson picnic bench just before getting started. The orange wire spilling from my backpack was a thought at trying 10m, but with less than two hours before Late Shift started, it was my priority to get the 14th activated rather than playing around with new wire configurations.

People have been making UART cloning interfaces for the single-pin serial on TRRS 3.5 mm plug to Yaesu radios like the VX-2 for years. Unfortunately, those years mean that many people were making RS-232 to TTL converters and waxing poetic about using two or more transistors to implement the level shifting between the ±5 V or more interface and 3.3 V for the radio. Heck, some even implemented a whole zener and PNP linear regulator to ensure a safe pull-up voltage was presented to the radio. But wait, we've got chips that go from USB to right where we need the signal levels… (Styled as a recipe blog post; skip to the end for the ingredients and assembly steps after the story)