On the subject of amateur radio, I am one. I'm also a new Flat Earther. One thing I want to point out that effects of methods of radio communication cannot prove the earth is flat or round. There are workable models for both. therefore we must proceed on other bases. This is basic logic.
By the same token, I would welcome anyone who can postulate on how radio long-distance communication can occur on the HF bands (1.8 Mhz - 28 Mhz) on a flat earth. I am thinking the firmament (which is a hard metal-like surface, likely) can accomplish this nicely. And the time of day and sunlight can and does affect it. I know of no other ham operators who believe in flat earth, altho I have read of a couple on the web. So anyone wanting to chime in on this, fel free.