It was presented at a QRP conference, after all (and I'm more of a QRO proponent) so I imagine the dinky capacitor didn't worry them too much.
My MFJ loop is working pretty darn well so far. I'm sure I'll have to take it down and fix it eventually, but I have 54 countries worked this year since I put it up in March. On Thu, 10 May 2012, David Cutter wrote: > I agree about the statement re height above ground which needed > qualifiying a little particularly as they then made measurements > somewhat less than that. The main thrust is about losses and the more > removed from ground and nearby objects the less the loss due to the very > high intensity of the electric field. Not sure if they specified a > maximum power handling and I didn't see anything about inter-plate > insulation so it was just dry air - (ie all the water is frozen on the > ground). That probably also means the ground was not as conductive and > lossy as it might be in the summer when the electrolytes are free to > move (my guesswork). Wouldn't work too well in our wet UK climate! > Great piece of analysis and engineering, deceptively simple. > > David > G3UNA > > On 10/05/2012 11:11, Arthur Burke wrote: >> I bookmarked the site - thank you. However, I didn't get very far the >> first time when I saw the comment "....must be 1/2 wavelength above >> the ground..." >> Still would like to go back and review the entire article. >> Brings back a humorous dialog from years ago. One ham expressed the >> desire to build a "....good, but short, 40 meter beam..." It was >> suggested he shorten the beam until it was ultimately a 50-ohm >> resistor of sufficient girth to accept reasonable power levels. >> Chuckles followed. >> Then, someone who apparently didn't pick up on the tongue-in-cheek, >> frowned and noted that the 50-ohm resistor would work even better if >> it was at least a couple wavelengths in the air. >> Art - N4PJ >> >> >> On Thu, May 10, 2012 at 7:30 AM, David Cutter <d.cut...@ntlworld.com >> <mailto:d.cut...@ntlworld.com>> wrote: >> >> It will be quiet on receive and quiet on transmit, however much power >> you put into it, until it melts, that is. I'd love to know where he >> gets his efficiency figures - perhaps you can ask him. Putting steel >> washers at each aluminium joint turned me off completely along >> with the >> dinky receiving capacitor. >> >> I'm quite taken by the Midnight Loop from N2APB and N2CX, mainly >> because >> I built something similar 20 years ago, only a lot bigger! See >> >> >> http://www.midnightdesignsolutions.com/MidnightLoop/Midnight%20Loop%20%28Mar%2011a%29.pdf >> >> David >> G3UNA >> >> >> On 10/05/2012 07:55, Stephen Prior wrote: >> > Hi Fred >> > >> > I have been very tempted by the Alex-loop, but in the meantime >> have just >> > bought one of G4TPH's loops which I shall put through its paces >> when the >> > weather improves! I should imagine that the insensitivity to >> electric >> > fields in the near field would be an advantage in electrically noisy >> > environments. Even a campsite can be very noisy with the >> inverters from RVs >> > and the like spewing out rf everywhere. >> > >> > I'm spoilt for choice of antennas to play with once the KX3 arrives! >> > >> > 73 Stephen G4SJP >> > >> > On Wednesday, 9 May 2012, Fred Jensen wrote: >> > >> >> I haven't been following this thread closely but has anyone >> mentioned a >> >> small magnetic loop like the Alex-Loop? I've got a good SOTA >> friend who >> >> uses one and loves it. >> >> >> >> 73, >> >> >> >> Fred K6DGW >> >> - Northern California Contest Club >> >> - CU in the 2012 Cal QSO Party 6-7 Oct 2012 >> >> - www.cqp.org <http://www.cqp.org/> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> <mailto:Elecraft@mailman.qth.net> >> >> This list hosted by: http://www.qsl.net <http://www.qsl.net/> >> Please help support this email list: http://www.qsl.net/donate.html >> >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > -- Hisashi T Fujinaka - ht...@twofifty.com BSEE(6/86) + BSChem(3/95) + BAEnglish(8/95) + MSCS(8/03) + $2.50 = latte ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
