[TowerTalk] Relay for sloper element

[Bryan Swadener]

Hi Gene,



On 80m, instead of changing the length, I increased the effective diameter by using a cage design. The free design program on smeter.net (http://www.smeter.net/antennas/wire-cage-dipole.php) says it looks like a 7.7" diameter conductor. My 2:1 VSWR bandwidth is supposed to be 318 kHz but, I'm seeing over 500 kHz. A sloper would work about the same.

Since the apex of my inverted vee is at 70' and I have about 85' of coax feeding it, I thought it worth trying to feed it as a vertical against a radial field on 160m. The ATU in my TS-850SAT is able to tune into it. I use a Jennings RJ1-series SPDT vacuum relay in a plastic box to do the switching. I use a "bias tee" to feed 13.8V from the shack power supply via the coax to the relay's 12VDC coil.

Related images and more info on my Flickr page: http://www.tinyurl.com/wa7prc-80m-160m

vy 73,
Bryan WA7PRC
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Date: Thu, 23 Nov 2017 12:17:33 -0500
From: "Gene Smar" <ersmar at verizon.net>
To: <towertalk at contesting.com>
Subject: [TowerTalk] Relay for sloper element

TT:

I want to be able to switch a piece of #14 house wire onto the far end
of a sloper wire I have for 75 M phone so I can operate lower in the band.
I'm thinking of adding a relay in a weather-resistant box at the sloper's
end insulator and continue with the extension wire beyond that.  

FYI:  The sloper wire runs from the 50 foot point on my tower to my
house roof where it is tied to an end insulator and thence to a PVC vent
pipe via a bungee cord.  The wire runs through tree limbs, hence my need for
a flexible connection.  I'm thinking I can mount the relay/box near the end
insulator and extend the additional wire further across the roof.  I'm
thinking I can run 15 +/- VDC to it from the station supply in the shack via

RG-58 coax up and across the roof to the relay box.  
My question to this august group:  What relay (and supplier) would you
recommend for the job?  

In the alternative, can you point me to a good source of info on
designing traps for said application?  The trap would not require any DC for
switching but might take more "cypherin' " to get working.  

Many thanks and Happy Thanksgiving to all y'all.

73 de
Gene Smar  AD3F