Re: And what of the FCC?

To: tesla-at-pupman-dot-com
Subject: Re: And what of the FCC?
From: Tesla List <mod1-at-pupman-dot-com>
Date: Wed, 1 Oct 1997 10:10:48 -0600 (MDT)
Approved: mod1-at-poodle.pupman-dot-com

---------- Forwarded message ----------
Date: Wed, 1 Oct 1997 19:35:39 +1200
From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
To: tesla-at-pupman-dot-com
Subject: Re: And what of the FCC?

Hi Randy,

<snip>
> All of these posts regarding RFI etc have caused me to wonder:
> What is the difference between a rotary gap TC and the prehistoric
> rotary gap CW transmitters? Is it just a matter of tuning a TC to 
> deal with an antenna instead of a toroid or sphere as the "load"?

The difference is in the degree of coupling to free space. A TC has a 
very high radiation resistance as its 1/4 wavelength is in reality, 
*the height of the secondary coil*. If that seems like a strange 
notion, think about it. Imagine running a very short antenna whose 
length is equal to the height of the secondary coil (tuned by a 
loading coil of course ;) at 500kHz. How efficient a radiator at 
500kHz will that be?

Malcolm