I have a TH7 and a TH6 and a HDR-300. I would not buy either again. Why?
When I installed my TH7 I was very carefull to install the trap covers so
that the holes were pointing down. After the first rain, the SWR on the
antenna went crazy and the antenna failed to act like a yagi. After 2
or 3 days of sun the antenna came back to life. I called Hygain and the
guy on that answered the phone said "Oh ya, if you live in an area that
receives hard rain, the end trap covers will fill up with water and short
the trap cover to the end of the element." When I asked why they didn't
put this in their manual or modify the antenna, I got silence and some
grumbling. This one small oversight caused me great pain to take this
antenna down through my pine trees.
The HDR-300 is the better story. Those of you familiar with this rotor
know that it has a shaft that sticks out of the top of the motor. This
shafts goes through the hole in a rotor plate and a molded base sticks
onto the shaft with a keyway. What they didn't tell me, was that after
a year in raining weather, the molded base will rust iself onto the
shaft. Once this happens, you will NEVER get it off. I talked to
local that has tried unsuccessfully to remove this piece from several
of these rotors and his only solution was burning it off with a torch.
He called them and asked them about the problem (this was several years
ago) and the said "Oh no, we don't know of this problem!" After I
experienced the same problem, I called them and got the same answer
from exactly the same guy that told my friend the same story two years
previous to my call. It's bad enough that they have a problem, but
not to admit it and cause great frustration to others is inexcusable!
Bill Fisher, KM9P KM9P@DELPHI.COM