Hello Lil Red:
I have a couple of the Hy-Gain Penetrator 500 5/8 wavelength base station antennas myself. I bought a few off the internet, some in great shape and a few not, .... a stick of Aluminum Tubing was straight.
Hy-Gain came out with the Golden Colinear, 5/8 wavelength in 1962 for $92.50, but because it had only a single point mount holding the vertical element, they all broke in time. Next came the CLR II that had 3 ground plane radials, (as did the first Golden Colinear) and a Mickey Mouse Impedance Matching Circuit, that was a etched circuit board, that the conductor was only .070 inches in width, and was etched in a coil. The CB'ers and Hams burnt out these inexpensive Impedance Matching Coils in droves.
Next Hy-Gain came out with the Penetrator 500, that was very well made, had a Top Hat assembly, 4 Ground Plane Radials, and a extenal Impedance Matching System. The Penetrator 500 came in three different configurations, two that measured 259+ inches from the base ground plane assembly, and the later one that was 257 3/8 inches, for the 40 channel radios.
I believe this was the only ground plane antenna that was ever rated to handle 1500 watts, which was what the typical Ham Linear Amplifiers would do, during the Penetrator 500 peak in popular time.
I would have loved to be in the meeting at the Hy-Gain Plant when they set down and said they need to design a antenna tha will take 1500 watts, I am sure there heated arguements, and things thrown.
I have one Penetrator 500 up and working that has to been up 30 years. Great Antenna.
Jay in the Mojave
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