SWLing Post Message Board

as for the CTL, did you consider changing the size of the sides ? I mean, for example, making the vertical size 1/2 of the horizontal (or the other way around) while keeping the same total perimeter

Welcome to the forum, qrp-gaijin! Hope you guys tell me when it's time to charge my little dremel tool. :mrgreen: ~20dB more gain / less losses at little more than 1/2 the size of the SULA sounds pretty intriguing, even though the overall coverage seems to be pretty small (7-21Mhz?). ...check if it...

forgot (and OT) do you know what happened to Jim's ham forum (the radio board) ? I know you were a member there, and there were a lot of cool folks, but then, it went suddenly "poof" <sigh>

first of all, at the moment I'm busy helping some relatives picking olives from trees, so please forgive me if I delay my replies; also, as you can guess. I've no way to run NEC simulations here :D (note: did you know that ezNEC is now free ? https://www.eznec.com/ ) ... anyhow, your simulations are...

forgot, (yes, still ferreting around <sigh>); try the following: load the CTL model, remove the cap/resistor from the outer loop and replace the cap in the inner loop with a resistor (530 Ohms like the SULA will do), now run the NEC model, done so, change the inner loop size and check the result, do...

I'm in a hurry, so I'll keep this short; first, that loop and dipoles setup somewhat recalls at large a yagi (dipoles), did you try changing the size/spacing of the dipoles ? Then, about the CTL, I started wondering if it may be used as a TX antenna, in such a case it would be interesting for lower ...

Thank you, ran the model and it behaves as expected, I just changed the "GN" card to put the antenna over real ground and not in free space ("GN 2 0 0 0 13 0.005") the results are pretty good, but the impedance is around 2 Ohm which means that, to couple the antenna to a receiver...

as for the directional lobe, check out the currents and phase of the CTL, that should tell us something, I believe

Secondly, at 1.8 MHz, maybe you need to significantly increase the both (1) the load inductance of the outer loop and (2) the intrinsic inductance of the inner loop. The CTL article says that for (2) you should use additional wire turns on the inner loop to increase the inductance, but that is a ve...

Thanks for the warm welcome. :) Well, I've been "following" you for some time and it's a pleasure to see you here ! Excellent to hear! Did you ever actually get around to building one? I have only simulated, but not yet actually built, the CTL. No, I just played with some NEC models but t...