"Dave" wrote in message
. ..

tv dx is basically a line of sight vhf/uhf type
of propagation where height is everything. the higher you can go the
better

Yes, this has been my experience -- I need to get higher than my neighbor's
roof, for example.

i don't know where 10 wavelengths came from since that is actually
pretty low on the higher uhf channels!

Another Yes. At 600 MHz (near mid-band for UHF TV) 10 wavelengths is a mere
5 meters. Not much of a skyhook required to get up there!

Doubtful this applies to HF skywaves. Thanks to all..

73