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Manager - AB7RG
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Three 'Musts' for Installing a Tunable VHF and/or UHF Vertical

Created by Phillip W. Harris, PhD.P.C. on 2022-11-10

I am confident that the following information can apply to HF verticals and other antennas also, but my recent experience in installing VHF verticals (the last one being a G7-144 2 meter monoband vertical) has shown me some things that bears sharing to make other installations go a little easier compared to what I just went through:


1. USE A TRIPOD FOR TESTING/ADJUSTMENT: this is the most important point I could stress. The antennas must be placed out in an open area away from all metal or anything else that could mitigate SWR readings. Merely leaning the antennas against a wall or laying it horizontal will create (sometimes greatly) different SWR readings compared to those readings once placed on/in its final position. I placed the antenna against a large cement garden pillar that gave me a completely different SWR reading than when I got it back on the pole. The pillar was full of re-bar that mitigated the signal/SWR. There was also a chance that the antenna could lean and fall with resulting damage. Evening having a friend hold the antenna during SWR measurement will affect the readings. I borrowed a speaker tripod from my Church and placed the antenna/tripod out in the street away from all metals. The SWR after adjustment was the same SWR that I got once the antenna was on its permanent support pole. You can pick up a tripod cheap (sometimes used) from a music store (Sam Ash, Guitar Center, etc.) or from Craig's list. This is the BEST advice I can provide anyone.


2. USE AN ANTENNA ANALYZER: Technology is the closest thing we have to magic. Beg, borrow, or buy one of the many different antenna analyzers on the market and make your life easier. In my case I borrowed a RigExpert AA-600 from a friend (thanks and a hat tip to Fred, KN6OS); this beauty shoots a signal at a chosen frequency and then represents the antenna's response to that signal in one of several different graphical ways. Gone are the days of adjusting the antenna and then putting it up and taking it down on its support structure while looking for minimum SWR on a SWAN WM-200A meter. These analyzers are a God send and worth the investment  as you will continually find yourself testing the antennas and feed lines to check any degradation of materials over time.


3. USE A SECOND PAIR OF HANDS TO HELP YOU: I am 72 years old and proud that I installed my G7 on a Rohn H40 by myself. Big mistake and I was lucky. The Rohn telescoping mast is well made and nests at ten (10') feet. The G7 is only ten (10#) pounds. Try lifting and balancing a fifteen (15') foot antenna while going up a ladder and keeping it balanced with one hand while placing the securing it on the mast with the other hand. I am fortunate it (or I) did not fall with varying consequences for such. A second person is greatly needed to help hold the antenna and all stages of installation.


I hope what I have learned over the years of putting up many verticals will be a benefit to those wishing to save time, lessen chances of damage to the product and/or injury to oneself and make the job a more rewarding experience once completed. Thank you for reading. Phillip W. Harris, PhD.P.C.


Three 'Musts' for Installing a Tunable VHF and/or UHF Vertical
Thank you for all the good advise. Especially about balancing on a ladder while trying to secure the antenna.
Again, thanks.