Enquiring minds want to know. I intend to raise a dedicated SWL antenna this fall along the edge of my property. The engineering and logistics of a T2FD is higher than for a dipole. Is it worth it?
My general experience with this T2FD is:
It works very well for the size. Performance is great down on MW, and up on 11 meters. If you have limited space and can only put up one fairly small footprint antenna, this may be the one. But you need to mount it nearly vertical (see below) for best results. This is good in that you don't need a lot of yard area vs a horizontal dipole. But you do need a tall tree, basically 85% of the length of the antenna assuming a 30 or 35 degree tilt from vertical. This means that in general you do not select the length of the antenna based on the band(s) of interest as with most antennas. Instead you find your tallest tree, get a rope over it, measure the length at that angle, and design your antenna appropriately.
It is not as good as a dedicated antenna for most single bands. My 43/48 meter band folded dipole wins on those bands, and nearby.
I *think* you want to mount it so that it is at about a 30 degree from vertical orientation, based on the signal plots in my previous post. I am not 100% sure the few dB of signal increase was due to the tilt, it is possible it was because the antenna was slightly higher overall. But further increasing the tilt angle *lowered* signal levels slightly, so I'd say I am 99% sure it was due to the tilt. I need to do some more experiments to see. Also this was on MW, it is possible results on HF are different. It's tricker to test on HF due to the typical fading of signals, longer measurement periods will likely be needed. But I think it's a safe bet that this is close enough to ideal.
It's not too much more difficult vs a traditional dipole. You do need twice as much wire and some spacers, I found 1" PVC worked great. And you want a 9:1 or 12:1 balun vs the usual 1:1 balun. In one way it is *easier* than a normal dipole - you only need to get one end way up high in a tree, the other end is tied off at the ground.
I am beginning to think two, or even four, T2FD antennas much be interesting for diversity reception. I had been considering doing this for some time using vertical antennas, but we know that traditional verticals, are, well, typically not as good (I am trying to avoid using profanity when describing vertical antennas) in the real world as theory suggests, mostly because you can rarely get a good enough ground system for them (unless your idea of fun is ripping up your yard to bury 50 or 100 or so quarter wavelength radials). But a few T2FD antennas is much easier to install. And they actually work!
