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Who needs a repeater when you have 500,000 watts?


WRKS279

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I stumbled onto this video on YouTube tonight about the WLW radio station that for a few years in the early 1940's ran with 500,000 watts of power.

 

https://youtu.be/CbHjcwIoTiY

 

It was so powerful that it covered about 3/4 of the United States, and extended considerably into Canada. In fact, Canada filed a complaint because it just overpowered one of its own beloved stations. WLW had to setup two suppressor towers to decrease their reach in that particular direction. Its quite a fascinating video. Enjoy.

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Well, not really, and 1000 kW is only 3dB more than 500 kW, so...

 

The tower, with 1 MegaWatt @ 490 Mhz (roughly around where UHF TV station transmit) is a whopping +90dBm; so, if you calculate the attenuation/loss in free space , since the tower is 1000 feet high in the air, and there are no terrain LOS obstructions within 4 miles, most likely....

 

So, you get roughly a -96dBm @ 490 Mhz attenuation/loss of those firebreathing +90dBm over a 4 mile distance, so, these CCR receivers are seeing a massive -6 dBm signal on the front end, only a few MHz off the channel frequency.

 

In comparison, your superduper 50W GMRS mobile is putting roughly +46dBm, so, at the same 4 miles, given roughly the same -96 dBm attenuation @462 Mhz, the CCR receiver is seeing your GMRS mobile as a faint -50 dBm, on frequency, but a few MHz away there is this firebreathing signal that will completely obfuscate the desired signal you're trying to listen. And if that 1 MW transmitter is on the "right" frequency, to mix with the 1st IF stage frequency (for the Superhets) to create IMD, then you'll have all sorts of reception issues, or no reception at all.

 

Basically, you're trying to hear a nylon string classical guitar, without amplification, over a pipe organ playing at full power.

 

G.

 

I am 4 miles from a 1,000kw UHF TV station on a 1,000 ft tower - I guess I am safe

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