Also the ARRL antenna handbook is a good resource. I would suggest you search the internet for end fed antenna as there is a lot of information out there. I am in the process of making the antenna more broadband by going to a cage type system. I designed and built the switching arrangement and the antenna system. I have an antenna relay on the mast which connects either the transmitters on the MN2000 tuner or the Icom on the AH4 tuner to the antenna. I don't have a counterpoise but rather use a ground connection from the 9:1 unun to the mast which is grounded well.
The end fed antenna has a 9:1 unun which tames the impedance. I also run an Icom 706 into an AH4 tuner which is mast mounted. I have a Drake MN2000 tuner for my Drake TR4, Swan 500 and Heathkit transmitters. Jim, I use an end fed antenna cut for 75 meters. Also when I speak of dipoles that includes inverted vee's. More separation is better but 39 inches was the minimum. Also one article on the fan dipole found that 39 inches (if I remember right) separation on each end of each element from the other dipoles would work. A 40 mtr dipole would also work 15 meters, an 80 mtr would also work for 20mtr (if memory serves me) so you would not need 7 dipoles in the fan if doing 80, 40, 30, 20, 17, 15, 12, and 10 meters. Verticals work well when you do not have the real estate available for half wavelength dipoles. HyGain (now MFJ?) still sell a couple verticals like the old (and may still be made) 18AVQ vertical which was good for 80 through 10 meters (but excluded the new WARC bands like 30, 17, and 12 meters). I had one up for about a month and worked great for receiving but was mostly a broadband "dummy load." It did radiate some rf but a lot of it went out as heat in the 600 ohm terminating resistor. The B&W style broadband antenna is one that is out there and claims to work from usually 3.5 up through 10 meters but it is one to be avoided. A 4 to 1 balun on the transmitter end of the 450 ohm ladder line would work and the antenna could be used on 80 up through 10 meters. At that time automatic tuners were not available in commercial radios and the radios of the time still leaned toward pi net output stages. In the 70's I bought an 80 meter dipole that had 450 ohm window line and it worked very well on all bands. I keep looking for the ultimate antenna but have not found it. A random wire has some wide ranges in impedance and does not play well with most automatic antenna tuners. Jim, I do not know what your real estate where you can put an antenna is like. I have been thinking of a long wire end fed antenna tuned with the optional antenna tuner put out by Icon or Yaesu.
#ICOM IC 756 PRO II AND G5RV ANTENNA PDF#
Take a look at some of the radio handbooks and books about wire antennas, I believe you can find quite a few PDF copies online.
Unless you know you will keep a specific rig for a long time then avoid rig specific accessories like antenna tuners that you have to buy separately since the acquisition cost will probably greatly exceed its resale value yet you won't be able to use it with future rigs if it is one that is completely wedded to and controlled by a specific rig.
There are a number of other wire antenna choices outside of a random wire that may fit your needs and real estate which would be easily matchable with a rig's built in or external accessory tuner. So a longwire for 40 meters would be 280 feet long A random wire antenna can work very well but it can also make issues like a "RF hot" radio room more likely. Most long wires are really better termed random wires, a true long wire is multiple wavelengths long at the frequency of operation. There are a lot of choices both current production and vintage classics.Ģ.
#ICOM IC 756 PRO II AND G5RV ANTENNA MANUAL#
Unless you absolutely must have an "automatic" tuner your needs will be far better served with a well made manual type external tuner. Most of the built in or external matching tuners for current radios are only designed to handle a slight mismatch and will likely not work well with your long wire.
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