Window Line Standoffs – JD style…
By JD Delancy, W1JD
Copyright 29 August 2024
My 160-meter Inverted VEE’s center is near the top of my 100-foot Rohn-25 tower. It is fed with 450-Ohm Window Line and comes down the North face of the tower. This one has been in the air for 12 years.
When the Vee was initially put up, the Window Line came straight down and was secured about 20 feet from the bottom of the tower. It worked fine – until the Autumn/Winter winds started blowing. One morning, I found that the previous evening’s winds had entangled the ~90 feet of unanchored Window Line around several VHF/UHF antennas (in the wind the Window Line was flopping around like a fish out of water).
After the second or fourth time, in the “BER” months, that I climbed the tower to unwrap the Window Line, I decided something had to be done. Pondering what could be done, invented, implemented easily and cheaply became a constant thinking task. All sorts of ideas came to mind but none of them really grabbed my attention.
One day I was in Lowe’s getting some plumbing supplies when I stumbled on a strange looking “TEE” that turned out to be a 1-in x 1/2-in Schedule 40 PVC Slip Joint Tee (SJT), Model #L464-130, (Lowes Item #188243). I wondered if it would fit around a Rohn-25 leg. I purchased one for a couple of dollars, went home to the tower, pushed the SJT onto a leg, and with a resounding “snap” sound – it fit! It was snug but a little loose. A two-inch Stainless-Steel hose clamp snugged it up tight, no movement.
Back to Lowes. The (SJT) side “outlet” is 1/2-in, comes in both threaded and slip joint for PVC cement gluing. Lowes was out of the slip joint type, so I settled on the threaded version. I found an adapter that enabled transitioning from the threads to slip, (Lowes Item #23855). Next, I found a 10-foot piece of 1/2-in schedule 40 rigid PVC non-metallic, Ultraviolet (UV) light resistant electrical conduit and a 1/2-in schedule 40 PVC plumbing “TEE” (Lowes Item #23873). Then the adapter, with PVC glue on its threads, was screwed into the SJT 1/2-in “outlet.” I cut a 20-in piece of the UV conduit (length is not critical less than 20-inches works), PVC-glued it into the 1/2-in “TEE’s” outlet and quickly rotated and set the TEE, before the PVC glue solidified, so that the 1/2-in “TEE” was at a 90-degrees in relation to the SJT.
I determined that I needed four home-brewed standoffs (HBSO) to keep the Window Line in place. My VEE’s feedpoint stands off away from the tower about 2 feet. I installed the uppermost HBSO about 2 feet below the VEEs feedpoint. I then installed each of the next three HBSO’s approximately 20-feet apart down the tower with the fourth and last one being about 15-feet above ground. From the top standoff down, the Window Line is attached at the front of the 1/2-in Tee. Two Extreme Weather Cable Ties (Utilitech 0650889) are looped through the Tee, “tail-to-head” and secured to themselves with the Window Line between the Cable Ties and the Tee.
At the bottom standoff, the Window Line then transitions to horizontal and routes to the back of the house and into my basement shack. The Window Line connects to an MN-2700 tuner and tunes everything between 160- and 10-meters and it handles my 30L1 amplifier (½ KW) fine. Cost for each standoff: about $5.
PICTURES:
 Slip Joint Tee, Lowe’s #188243, $2.82 |
Thread to Slip adapter, Lowe’s #23855 $0.76 |
1/2-in PVC Tee, Lowes #23873, $0.79 |
One of the my “originals” on the tower |
The final product. It’s ugly but works good! |
Securing the Window Line to the TEE’s FRONT |
