Cant wait for a bit 11 metre activity. In fact a vertical shows no marked improvement in low angle radiation. As a bonus, you get a gain antenna with a pattern oriented in the directions of service chosen, not a bunch of random lobes. Basic antenna theory has not changed a bit from that time, other than having better computer modeling. They use three complete dipoles in one package. The original Jetstream Multiband 80 - 10 Dipole never had coverage of these bands. One leg is 67 ft.
It is likely also to compromise performance. Listening tests confirm this initially. The typical bandwidth is: 160M 20kHz 80M 40 kHz 40M 300 kHz Full band coverage can be accomplished with an antenna tuner. Open wire feeders and single wire feeders are rejected for this reason also. Not easy to find it locally. This design came from attempts to find an 80m antenna that could fit into a small space. Try inserting a short length jumper 3 ft to see if the rig's built in tuner will match.
I used the standard cap to keep the water out of the top, and bugs out of the bottom. It also is up high enough for 80 meters for local work. Alpha Delta and Jetstream sell multiband fan dipole kits. I will use no other on any wire antenna. Lots of interaction between various bands.
Same deal for the Alpha Delta. Once again, build your own, save money, and get better performance! Incidentally, I did not use the cheesy plastic end insulators included. The longest element is just 29 ft long! Drill as small a hole as possible for the wires in the spreaders to keep rain and bugs out. I do not know if it was a voltage balun. Significantly, the reactance curves show very little of this component.
One of these options should be good enough for most configurations. When you have your antenna tuned and working, put the tuner in a housing like a Tupperware container. I use two separate end ropes to the same tree on my installation on Long Island from the 80 and 40 antennas. From looking at past posts, Steve looks to be very forthwith with answers if you happen to have any questions about the antenna. To build this antenna you need a lot that is at least 100 feet across. The black connector has a turns ratio of 6. The article above noted comments on the minimum spreader length needed to get good performance, and I followed that advice to advantage.
Use as inverted vee or sloper to be more compact. You can see in the picture the antenna has not been tuned, in fact the new end spreader bars have not been installed and tension devices haven't been adjusted. In fact, the separate Loop article on this page shows my 160 meter loop antenna. The last 20-25 feet had to run along a wooden fence. Simply cut two equal lengths of stranded copper wire. Easier on your radio too. Use coax seal, or Duct Seal available at electrical supply places like Lowe's to cover the coax connector, and you have a really reliable center connection.
The system would not take more than a few hundred watts at these frequencies before the amp faulted. It's strong, silky smooth, and anti kink. I replaced the wires to make it 135 ft. This should be about 1:1 in the middle of the band, and 1. Stainless steel hardware is included.
I have 4 foot spreaders on the ends at the 40 meter end point. The inductive portion of the trap also serves as a loading coil, shortening the needed length of the antenna; but it also reduces bandwidth. You must keep it clear of large pieces of metal a few inches at least. Maybe a push up mast. I use 80 on top, 10 next, 20 lower, and on the very bottom 40 Meters.
There is interaction between the various antennas in the mulitband dipole. They also perform well on their design frequencies. These are going to be the two halves of your dipole antenna. This provides a drip ring that keeps water out of the coax. A properly installed vertical is an excellent antenna.