Kenneth G. Gordon,
W7EKB's

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My Hornet Beam Antenna.

 

Below are photos of a three-element tri-band beam I have had for a number of years, but could never get to work correctly. I sent photos of this antenna to Mosley as I suspected that it might be an early version of their TA-33. However, their reply was that it most certainly was never one of their antennas. Recently, a member of one of the amateur-radio related forums of which I am also a member suggested that it might be a TET tri-bander. He asked me to send him photos of the antenna, which I have done. It turns out that the antenna is not a TET either.

Since then, I have discovered that the beam is a "Hornet", and possibly their model HT-500. I now have a "manual" of 4 pages for a similar model, the TB-750.

The dimensions and material of the antenna are as follows:

Boom: Steel tube, 1.5" in diameter, two pieces, total length 14 feet. The length of the boom for the TB-750 is 18 feet, so my beam is most likely not a TB-750, but perhaps an HT-500 or the later TB-500.

Each element center section: 12 feet long, aluminum tubing, 1" in diameter, thick-wall.

Coil-"cans" 1.5" diameter: Driven element and reflector coil-can length, 18". Director coil-can length 15".

Each coil-can has a longer piece of aluminum tubing extending from the inner end by about 3 feet, and from the outer end by 1 foot.

"Stinger" on the ends of each element are about 4 feet long.

Overall length of each element as presently adjusted is as follows:

Reflector: 27' 5"

Driven Element (a dipole, made of two pieces, one of which is clamped to the center-support, while one is insulated from the boom by thick pieces of hard plastic or fiberglass): 26' 10"

Director: 25' 7"

Distance from driven element to reflector: 84"

Distance from driven element to director: 86"

Here are the photos:

The 1/2 driven-element on the right is clamped solidly to the boom: that on the left is insulated from the boom. I will mount a current-balun at this point and will feed it with RG-213 coax.

The slots on the ends of the traps are to adjust the center frequency of the resonance at the center of each band for the CW portion (all the way out) to the 'phone portion (all the way in), and for tweaking either resonance to the operator's favorite part.

My antenna had been set to center on the CW portion of the 20 meter band, and the phone portion of the 15 meter band. I will replace the rusted lock-screws with stainless steel versions, and will clean all the rust and corrosion off the antenna, then will reassemble and test. It should be mounted at least 40' high. I'll do the best I can. I have a good rotator for it which I will have to dismantle, service, and reassemble before using it.

I have received considerable help from several folks to reach the conclusions I have. Some were on the ham-antennas "at" yahoogroups "dot" com list, others were from other lists I am subscribed to. A member of the ham-antennas list pointed me to a "manual" of 4 pages for the TB-750, for which I am sincerely grateful. I am now going to "attack" the various bits, first to clean them all up, then to dig into it with one of my GDOs. If anyone has any more information on the Hornet HT/TB-500, please contact me. I can be reached via my e-mail address show on QRZ.com. Thanks, and vy 73, Ken W7EKB