G-QRP Club 2020 Convention : The John VE3IPS - The Misunderstood Terminated Tilted Folded Dipole

[@roylaufer9233]

I think the T2FD is still a little misunderstood. At one point the presenter suggests that his modular design will allow him to include, in addition to his T2FD, a traveling wave element. The thing is, that a T2FD IS a traveling wave antenna. It is a non-resonant, non-standing wave, traveling-wave antenna (any reflections are attenuated by the non-inductive loading resistor. This is why the use of loading coils or traps that might be beneficial in resonant standing wave antenna designs would be counterproductive for a T2FD's traveling wave design.

[@mattbates6887]

Certainly one of the major advantages of my 90ft T2FD on 40 and 80, is the much lower noise pickup compared to my Delta loop antenna. In this case the T2FD with less gain is certainly an advantage. Signal levels are a little down overall on the T2FD, compared to my 40M full wave Delta loop, but this is easily resolved with an in line receive RF amp, giving a much better S/N. During the grey line period, when conditions are favourable towards the US at night, as they have been recently, I can easily copy US hams. I expect when propagation conditions improve this summer towards South America, I will easily be able to copy many more DX stations from this area. My slightly inverted ( not tilted) T2FD, is orientated E/W, which is probably why it consistently works so well in that direction. So it is certainly worth experimenting with a T2FD, as I found out before I even gave it any thought at all.

[@mattbates6887]

@goinghomesomeday1 Yes you're probably right Gerald, I wouldn't think the terminating resistor has much effect on the total radiated power. I would say on the higher HF bands, height above ground becomes far more important for the T2FD, while minimizing localized obstructions at lower angles. But as an NVIS antenna it performs very well indeed, with a much lower noise level than a Delta loop or Dipole on receive. If there are any power losses at all, it's very marginal to say the least. You can always wind the power up anyway. 73 Matt

[@boo-ix]

thanks for the info. been looking for something like this for some time. thanks

[@johnhess351]

I am pursuing design of T3FD fed with 450 Ohm window line placing balun at radio end. This should reduce overall line loss and get it back closer to on par with a standard dipole. May get increased lower freq bonus with availability of feedline as radiator but maybe scary multibanding down to 160 with no choke-ability in feedline.

[@EI6DP]

Hello John - To efficiently work on 160m you will need to have a full-size T3(2)FD antenna. The 90 foot version will work somewhat on 160m but the performance will be way down. I would love to run a T3FD but I am badly restricted for space. I have been using a T2FD for many years now and despite the many negative comments about the T2FD I find it a really great antenna.

[@jennerwein5971]

its very wideband, its easy to fit in small gardens (in short version), its good for data (ft8) & cw, its low-noise against qrm = but is not very strong in radiation similar to a 1/2 half wave dipole for sure ;-(

[@wildbill1]

This seems similar to a terminated end fed vee antenna. Just different orientations and it’s fed in the center.. assuming it’s also a Omni directional antenna

[@PatAutrey]

I just wanted to comment and let you know you did a great job on your presentation and I enjoyed the material quite well You mentioned on the video that you were going to be making some assorted Baluns to experiment with I was wondering if you could show me how to make at 12 : 1 I have been looking for plans for this not found anything to show me how to do it