In article ,
"Brenda Ann" wrote:

"Telamon" wrote in message
...

6 1/8 inch is what most radio stations use?


Pretty common for FM and TV stations.. not so much for AM. IIRC, 1520 in
Portland used 3" Heliax for 50KW.

Someone wrote that 50 ohm was standard. Why am I seeing 75 ohm
components then?

And while I'm back on the impedance subject I expect that tower
impedance can be much lower than 50 ohms so that why a matching network
is needed at the antenna?

--
Telamon
Ventura, California