Re: Homemade open-wire line for QRP (Trouble Free H.F. Hertz Antenna for the Apartment Dwelling Ham)
The described open-wire feedlines seem fit only for light duty and probably indoor use.
Years ago I measured a 10-foot length of windowpane, so called "open-wire" line, and found it to be 58 percent closed because of the unnecessarily wide pieces that are between the open spaces.
I got a bag of bamboo skewers fom an Asian food store, cut them to 2.50" length with a 0.25" notch at each end. I fitted #14 gauge soft drawn copper wire into the slots, securing it with a piece of 50 lb. Dacron kite line tied with a constrictor knot and then doped the knot with a small gloh of epoxy. The bamboo spreaders were spaced at intentionally variable distances ranging from 9 to 13 inches. It survived several NJ winters.
With a yet-to-be erected antenna calling for a balanced feedline, my next open-wire will use the same method, but l will use hard-drawn #14 bare copper wire instead of soft drawn. The idea is that with the hard drawn wire I can get by with longer distances between fewer spreaders. This because the hard drawn wire will be more able to keep its shape and its spacing from its parallel conductor.
Charles (aka Chas), W2SH
From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of John <kk4itx@...>
Sent: Thursday, January 10, 2019 12:14
Subject: Re: [4SQRP] Homemade open-wire line for QRP (Trouble Free H.F. Hertz Antenna for the Apartment Dwelling Ham)
What a read !
I too use magnet wire but (18ga) in fear of breaking from birds and wind but will give 26ga a go now that the tree is gone. I have 100ft of 450 ladder that I may try also using foam pipe insulation to keep it away from the metal roof.
Thanks for sharing the link.