[Elecraft] Subject: Re: Ladder line changes when wet (was KAT500...)

[Joe Subich, W4TV]

On 2025-07-21 2:08 PM, Ed Cole via Elecraft wrote:

> Now thinking to convert an old copper-clad steel-wire 80/40m fan
> dipole to a G5RV and use some 450-ohm open ladder line for the feed.
> (Forgot I had that when making the 80m FD).

I would recommend against shortening the 80m element.  You can certainly
convert to open wire/window line all the way to the tuner or to a balun
on the outside wall of the shack but don't shorten the element as the
feed impedance and efficiency drop rather quickly on 80 meters.

If you must do a G5RV type antenna make it double size (204 feet with
68 ft window line).  It will be much more efficient on 80 and easier
to match on 40/30 meters.

73,

    ... Joe, W4TV


On 2025-07-21 2:08 PM, Ed Cole via Elecraft wrote:
> I made an 80m folded dipole using 450-ohm window wire (with 16ga
> single-conductor copper).  Wind whipped it so much the wire broke inside 
> the insulation in five places.
> 
> I replaced one side and the approx 30-foot window wire feed line and
> repaired a couple breaks in the other side.  I found window wire with
> multi-conductor wire from DX-Engineering which I hope survives better.
> 
> I use a DX-Engineering 4:1 Balun at ground end of feed for approx 120- 
> foot RG-213 coax to KAPA100/KATU100 driven by my K3/10 (also have a 
> KX3).  1200w W6PQL HF/6M amplifier to be built this year.
> 
> Now thinking to convert an old copper-clad steel-wire 80/40m fan dipole 
> to a G5RV and use some 450-ohm open ladder line for the feed. (Forgot I 
> had that when making the 80m FD).
> 
> 73, Ed - KL7UW
> https://www.kl7uw.com