Ground System Importance

[Schroedingers Cat]

Dan wrote:

"But those two statements (207.8 degrees and 362.1 mV/m/kW @ 1 km) are inconsistent with each other. A radiator that tall would have an efficiency of about 420 mV/m/kW @ 1 km. Even with a seriously substandard ground system, the efficiency of a radiator that tall would exceed 362.1 mV/m/kW @ 1 km."

My point exactly.  Oldtimers who remember the 225 mV/m per kW @ 1 MILE would see it immediately if they saw 225, realizing that that would correspond to a radiator some 10% less than 180 degrees, which is the Class minimum height requirement according to that particular graph.

[boiseengineer]

Don’t think the limits KOA had prior to the revised treaties in the 80’s is in effect anymore. Same reasons the protection of class A's in the US was relaxed.

According to KOA they do not have a resistor in line.

But hey, the FCC database is never wrong, is it? They still have an AUX license of ours in there that the license was turned in - deleted 9 years ago.

This is fun reading.
Final Acts, of the Regional Administrative MF Broadcasting Conference (Region 2) Rio de Janeiro, 1981
http://www.tzsawyer.com/pdf/rj81.pdf

[Schroedingers Cat]

If KOA doesn't use a resistor then either:

1) they reduce the power to the antenna and have minimum Class A efficiency or

2) they put 50000 watts to the antenna and have an efficiency consistent with the 207.8 degree tower and the FCC Query result is wrong, both the resistor comment and the efficiency.

I've seen other records that I suspect were messed up like that.

[radiorob2.0]

There is a thread on the Indiana board about the former 1400 WROZ Evansville.  I copy the comment here since it is of relevance of this thread:

"Before the move to the river, the tower and transmitter were on top of the old YMCA building downtown. The copper strap ground system ran down the sides of the building, and then was quietly bonded to the water main below ground which helped the signal considerably. As a kid up in Princeton, I could copy them day and night. But after they moved out to the river, the signal level was never the same. OK during the day, but a no-show at night."