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Radio station reception

Hi
I read a lot about the compression of a radio signal affecting overall quality and enjoyment of radio broadcasts, but dont have any idea if the station I listen to does this or not, or to what extent.
I listen to KMFA, a great classical station here in Austin Texas. I have a Magnum Dynalab MD100 tuner linked up to 2 Marantz SM17SA in BTL mode and Adcom GFP 750 pre amp powering Sonus Faber Concertino's and Kef RDM3's. The station sounds good to me compared to my CD's through a Sony SCD 777. I have attached a link with KMFA's technical specs... could someone interpret them for me.
http://www.kmfa.org/about_tech.asp

By the way, I live around 5 miles from transmitter and seem to receive a clean signal with little effort.
peteinvicta1
peteinvicta1 OP
22 posts
 
Thanks Sean
I have seen quite a few of your replys on Agon and you always seem to 'know your stuff'...
Thanks for all the detail... Based on what you say, it seems I am getting a pretty good signal from KMFA. I actually use one of the MD whip antennas you mention.

Thanks again for providing me with a primer on the subject.

Peter
muzikat
932 posts
 
Sean,
Very informative as usual.

Pete,
If you are interested in an antenna that will take advantage of circular polarization check here.
ccrane.com/fm_reflect.asp
Cheers,
sean
6,231 posts
 
I forgot to mention something about their power rating. While they say that the amp is rated for 30 KW ( kilowatts ) of output, my experience is that commercial duty broadcast amps are VERY conservatively rated. As such, the 84% of rated power output that i quoted is actually a much higher percentage than what it is probably capable of.

I have seen commercial broadcast tubes maintain power output levels appr 4 times their rated output. That is, so long as the antenna was properly tuned and adequate "ram air" cooling was provided. Otherwise, the tubes go into "thermonuclear meltdown" pretty rapidly when pushed like that.

With that in mind, they might be able to crank up their power to 50 KW actual output and still stay within tolerance. Obviously, tube life would be shortened, but they would have doubled their effective power. While going from 25,000 watts up to 50,000 watts seems like a HUGE increase, it is really only a 3 dB jump in power. Kind of like going from 2 watts to 4 watts. Due to all of those zero's though, it just seems like a LOT more : ) Sean
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