I know this is an old thread, but I believe it is worth re-opening. The YEC concept of the one-way speed of light using the Anisotropic Synchrony Convention can actually be tested, despite what is commonly believed. And, in fact, it already has, but no one else aside from me has apparently figured this out. I am in the process of writing Jason Lisle, the original author, and seeing what his thoughts are.
However, unless you believe the moon landings were a hoax, the lack of delay in radio transmissions from earth to moon and back is evidence that ASC is correct. Moon hoax conspiracy theorists actually use this as evidence that the moon landings never happened because they note that there is little to no delay in the original broadcast transmissions. This lack of delay confirms ASC.
So, yeah, radio communication is an easy way to test the one-way speed of light. You just need a large enough distance to test it. You don't measure it directly, but the delay in response is the indirect method to test. Because each transmission is a single way only.
Now you're wondering "Why didn't I think of that?"
However, unless you believe the moon landings were a hoax, the lack of delay in radio transmissions from earth to moon and back is evidence that ASC is correct. Moon hoax conspiracy theorists actually use this as evidence that the moon landings never happened because they note that there is little to no delay in the original broadcast transmissions. This lack of delay confirms ASC.
So, yeah, radio communication is an easy way to test the one-way speed of light. You just need a large enough distance to test it. You don't measure it directly, but the delay in response is the indirect method to test. Because each transmission is a single way only.
Now you're wondering "Why didn't I think of that?"