[600MRG] Loops

[Pat Hamel]

Actually, The gap in the loop shield does not need to be in the top.
There is an electrical fitting used to mount and seal flexible rubber
covered (S-O) cable to a conduit box.
The loop I have been using for 10 years or so has an 8 inch by 8 inch by 6
inch conduit box with two of these fittings (one on each side) and a piece
of old heliax about 30 feet long running (looping) from one to the other. I
use the center conductor as the antenna and ground only one end of the
shield. I believe I saw the antenna described in an English WW2 radio
direction finding history book and used the S-O fittings to make mine
insulated and watertight.
Some PVC pipe running (almost) vertically from the box keeps the loop from
flopping sideways.
We can't send attachments on this reflector, but you get the idea.
73,
Pat W5THT & WD2XSH/6



-----Original Message-----
From: 600MRG [mailto:600mrg-bounces at w7ekb.com] On Behalf Of stoskopf at tri.net
Sent: Tuesday, February 16, 2016 4:48 PM
To: 600mrg at w7ekb.com
Subject: [600MRG] Loops with ribbon cable

I totally agree with comments about ribbon cable:  high inter-turn
capacitance and small diameter wire.  Surprisingly some years ago I bought
at a flea market a 1 meter square loop, actually 2 at 90 degrees, made of
heavy 1 inch aluminum pipe all welded to a box at the bottom and with a
molded block of plastic at the top for the shield gap.  Inside is a ribbon
cable with perhaps 10 wires all connected in series.  Used it for a while
on the blitzortung project and worked OK.  Thought about restringing it
with litz wire, but too lazy.  N0UU


_______________________________________________
600MRG mailing list
600MRG at w7ekb.com
http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com