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Worton tower project report
by Bill, N3DOU
April 4 2019
Proper feed line bonding and grounding where our feed lines enter the building was pretty much non existent. I provided Stellar with a BOND BAR, 8 foot copper ground rod and ½” feed line ground kits.
Stellar drove the ground rod in, cadwelded a #2 copper conductor to it, used a ¾” PVC conduit I provided to protect the ground, mounted the ground bar, secured and rerouted the electric bond and terminated all of the above to the bond bar.
I had Stellar provide a 7/8” ground kit for our new VHF feed line so it is properly grounded at the top, before it leaves the tower and now before it enters the building. We provided the 2 ground kits used on the tower.
We had Stellar tower sweep our four UHF ½” feed line and confirmed what we all ready knew that three of the four feed lines had very high SWR using their TDR. I had them identify the four ½” Link receiver feed lines. Once we identified the one good ½” feed line they went ahead and installed a ground kit at the building for that cable that tested good.
There multiple very interesting failures with the other three feed lines noe of which was the feed line itself.
- Water in 2 of the YAGIS which we replaced them both.
One was a new in box exact replacement and one was a used UHF YAGI we had in storage.
- 2 Connector mismatches!!! The feed line to the top had a ½” UHF female connector and the jumper to the antenna was a male N connector. The insulator between the center conductor and the threaded portion on UHF female connector had to have been removed and the Male N connector will thread up but there is NO connection between the 2 center pins !!!!!!!!!!!!!!!!!!!
- One jumper to the antenna was defective as well.
So they replaced the UHF connector with the correct N connector.
Once the 3 remaining ½” feed lines were tested good they went ahead and installed ground kits at the building end on them.
Now all 5 of our antennas at the 100 foot level all test good.
The only feed line ground left is at bottom of the tower. I left the ½” ground kits on site for them to install on a possible return trip.