How is (was) that possible? Do you mean triangulation and confiscation?
It was voluntary. Because it was war, and that's what hams do in a crisis. They are part of the solution, not the problem.
/johnny
“As for ham radio, they could shut that down, just as they did in WW2,
How is (was) that possible? Do you mean triangulation and confiscation?”
Remember, it was the 40s.
Back then Americans were Americans.
I doubt there was much need for the government to run around with DF loops.
There was just a legal ban on Ham Radio activity.
I was too young to have been a ham then, so I do not know all the details.
The last potential limitations that I remember were in the late 50s.
All ham stations were to have a Conelrad detector.
If all radio was to shut down, you would know from the Conelrad system. This applied to commercial and all other radio.
And many were drafted into special projects and practical vhf radio and radar came out of WWII.
/johnny