I am currently using a dual band dipole (well actually it is more of an inverted vee) on the 75 and 40 meter bands. The antenna center is at a height of approximately 30 ft due to my subdivision CC&R restrictions. I am only allowed to have antennas that are no more than 6 ft above the highest point of my house. In my case the highest point is my evaporative cooler at about 25 ft high. The 75 meter antenna is tuned for approximately 3900 KHz and has a 2:1 SWR bandwidth of approximately 180 KHz. The 40 meter antenna is tuned to the center of the band (7150 KHz) and has an SWR of less than 2.2:1 across the entire band. Both antennas share a common center insulator/feedline. The antennas are fed with 60 ft of Belden RG8X coax. The antennas were modeled using EZNEC for Windows prior to installation and both antennas appear to match their models very well. Predicted bandwidth and actual bandwidth are very close. Since both antennas are close to the ground (less than 1/4 wavelength high), most of the signal is radiated straight up. For the close-in operation that I do most, this pattern works out very well. I check into several Southwest USA emergency orientated nets on 75 and 40 meters and find this antenna works well. I get excellent signals reports from all around the Southwestern USA using this antenna and operating with less than 100 watts of power.
EZNEC View of antenna showing 40 meter currents
EZNEC View of antenna showing 75 meter currents
EZNEC Plot of 40 meter pattern
EZNEC Plot of 75 meter pattern
The 20-15-10 meter band antenna is a Mosley TA33 Senior 3 element beam. It is mounted on the top of a free standing US Towers MA-40 crank up tubular tower with a rotating base. The optional raising fixture is used to tip the tower over for antenna servicing. The entire tower/beam combination is rotated by a Yaesu G-1000SDX rotator mounted at about 2 feet off the ground for easy servicing.
The 2 Meter/440Mhz antenna is a Hustler G6-270R that works quite well.
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