Re: [IRCA] Yes, SAH!

["Bill Harms" <wharms@xxxxxxxxxxxxxx>]

I have accurately measured an SAH to 0.022 hz or once every 45 
seconds.  On 560 a couple of years ago I caught two stations beating 
against each other at regular 45 second intervals and have a 
graphical representation of it.  If anyone is interested I will try 
to locate the file. 

Bill Harms

On 15 Jul 2006 at 10:38, Charles A & Leonor L Taylor wrote:

> 
> 
> SAH= subaudible heterodyne= CARRIER BEAT= a frequency way below audible 
> frequencies =0.0 - 15 Hz or so.
> 
> The further two r-f frequencies are from each other, the greater the 
> frequency of the heterodyne.
> 
> If one station on, say 1000 kHz (1,000,000) is 1 Hz away from another, 
> 999.999 kHz (999,999.0) or 1000.001 kHz (1,000,001) the two make a carrier 
> beat of 1 Hz. If one moves, drifts upwards, somewhere around 20 Hz there 
> will be heard a heterodyne.
> 
> The lowest frequency audible by people is 20 Hz, and that's where the FCC 
> set the frequency tolerance. ITU went one better and set it at 10 Hz. But 
> as a percentage, fewer stations outside NA and central Europe hold that 
> tolerance.
> 
> Most US & Canadian station run closer than 5 Hz of exact center.
> 
> An offset of 10 Hz will cause a "gurgle" in the modulation of the two stations.
> 
> Perfesser Chuck 



_______________________________________________
IRCA mailing list
IRCA@xxxxxxxxxxxxxxxx
http://arizona.hard-core-dx.com/mailman/listinfo/irca

Opinions expressed in messages on this mailing list are those of the original contributors and do not necessarily reflect the opinion of the IRCA, its editors, publishing staff, or officers

For more information: http://www.ircaonline.org

To Post a message: irca@xxxxxxxxxxxxxxxx