On Mar 1, 5:58*am, dave wrote:
On 03/01/2011 12:35 AM, wrote:
On Feb 28, 9:12 am, *wrote:
My large horizontal loop requires no aiming nor tuning. It is for SWL
and amateur receiving only. Set it and forget it. QRM was the main
problem. It is 95% solved. I never (never) hear light switches (which
cause huge explosions on my ham radio) or the oscillators in my analog
TV; and like that there.- Hide quoted text -
- Show quoted text -
Horiz. sweep circuits in the CRT based units are extremely rich in
harmonics . You must have built an extremely successful product . Any
details/schematic available ?
Length feet = 1005/frequency of interest
Make area inside the loop as large as possible. Get it up in the air
(although under the eaves will work if you don't have a lot of metal
flashing.) It seems to be deaf to most QRM generated in the "near
field", so I have it 3' above my roof, generally in the same shape as
the house, parallel to the ground. I cut the loop and put an MFJ-913 4:1
current BalUn, 'cause that's what I had lying around. For receive you
can get away with a reversed CATV BalUn.
It wants to be balanced. Use ladder line, twinlead, or a BalUn with coax.
This article is only about half bull****:
http://n1su.com/loop.html
SkyWires · SkyWire Loop Antennas
http://groups.yahoo.com/group/SkyWires/