My subscription to Life expired, but I still have a subscription to Mad.

Sunday, June 25, 2017

Antenna Revival

I have a lot of vintage aluminum squirreled away in various locations on our premises. All of it is of the VHF and UHF variety except for one, a Hy-Gain 18 AVT/WB-A vertical intended for the 80, 40, 20, 15 and 10 meter HF bands. I bought it new in November 1980 for $81 and installed it at my old folks' home, but I seldom used it because I had a TET HB43sp 4-element beam that I favored for 20, 15 and 10 meters and I almost never got on 80 and 40. When I moved out of my old folks' home in the fall of 1983, I disassembled and packed up the Hy-Gain and never used it again.

Considering all my antenna choices, I thought about the Hy-Gain and wondered if it was a viable option. I found it in pieces in the shed and was surprised that it seemed to be in decent shape; most of the nuts and bolts were rusty, but otherwise, just dusty. However, there were parts missing ― the U-bolts for mounting the antenna and the four radials of the antenna's top hat.

None of the U-bolts in my hardware collection were the correct size, so I visited a big box hardware store, but none of the U-bolts they sold filled the bill. I probably will find what I need somewhere online, but in the meantime, I decided that two or three hose clamps would do the job temporarily.

Replacing the radials was more problematical. My plan was to use some Copperweld that I had on hand, straighten it as best as I could and solder ring terminals to the ends of each radial for mounting to the antenna. The only problem was that I did not know the proper length of each radial.

Reading various online top hat articles, it seemed the longer, the better was the recommended length for the radials. So I cut each radial to 24 inches, a length that was long, but not so long that the radials drooped much.

The weather finally cleared mid-morning on Field Day, so after lunch I assembled the antenna in about an hour and had it up in the air by the mid-afternoon. I did not have time to run a coax cable into the shack, so I brought the shack outdoors and connected my Elecraft KX3 transceiver to the antenna with a 25-foot run of coax and operated from my deck.

I went up and down the bands just to hear what I could hear and I was happy with the results. Reception with the vertical was on par with my 80-meter inverted Vee.

Next, I checked the SWR on each of the five pre-WARC bands and the KX3's internal antenna tuner was able to tune the antenna to 1.5:1 or better on each band.

I connected a microphone to the KX3 and began answering Field Day CQs transmitting 5 watts using the KX3's internal battery (1B Connecticut). I did not work all the stations I called and I did a lot more listening that transmitting, but in about 45 minutes, I worked a half dozen stations on 80, 40 and 20 meters. Nothing on 10 or 15 ― 15 meters seemed dead and the activity on 10 was sparse.

Overall, I was very satisfied with the antenna revival and plan to include the Hy-Gain as part of my antenna farm.  


  1. The newer model 18AVQ-II has ten 36" capacitance spokes for
    the 80 meter band.

    Mike Schaffer