From: "Mike Dennison" <mike.dennison@rsgb.org.uk>
To: rsgb_lf_group@blacksheep.org
Date: Mon, 26 Jun 2000 12:30:58 +0100
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII; format=flowed
Content-Transfer-Encoding: 8bit
Subject: Re: LF: Re: Sleep mode antenna
In-reply-to: <2000062410122668199@zetnet.co.uk>
Message-ID: <E136XF9-0006bQ-00@mserv1d.u-net.net>
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Sender: <majordom@post.thorcom.com>

> > Here in Sydney Australia we have (had) a CFA installation in commercial
> > use. I have done relative FS measurements (single point) at a distance
> > of 60Km and can report that the CFA antenna is NOT working as the
> > inventors say it will.  
> 
> In my early days of Ham radio I visited a radio ham who used one of 
> those old metal spring double beds as an antenna. The bed was 
> connected to the hot end of the ATU and the other to the water pipe 
> of a sink that was also in the room. As I recall he seemed to work 
> around the UK on 80m using it. I called it the Sleep Mode Antenna (SMA).

Many years ago, RadCom (actually it was the RSGB BUlletin in 
those days) ran a superb April spoof. It described an antenna 
comprising two circular plates joined by vertical bars like a cage. 
The clever bit was that the bars were spaced logarithmically from 
each other. More complex calculation went into where to attach the 
feedpoint - a single wire - off centre of the lower plate.

This was all fascinating and believable until you got to the final 
sentence whch said that for best results the single wire feeder 
should be vertical and at least a quarter wavelength, tuned against 
a good ground.

This was probably aimed at a popular short loaded antenna of the 
day called a Joystick, but which was also called the VFA (variable 
frequency antenna).


Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm