/\ Is a "BIG" no-arc with high SWR coax-fed antenna tuner really good? In seeems to me that high SWR on coaxial transmission line is Not good engineering practice. Open-wire transmission line is ide
/\ chortle/ I agree. Part of the problem could be the human tendency to shut eyes & endorse all things that they spent much of their money on. /\ Indeed - which would have rather happily have lowere
You can find a great image of the Measures balanced tuner at the following link. This "real man's" tuner was constructed by Matt, KK5DR. Nice job Matt! http://www.qsl.net/kk5dr/Zepptuner.html -Paul,
Here's a link to a photo of another awesome tuner provided to me by Phil, K5PC. Phil's design is similar to that as shown on the cover of the 1999 ARRL Handbook. Phil's tuner uses a balun at the tune
/\ More C (and less L) usually means more circulating current - which in turn means higher Q. cheers - R. L. Measures, 805.386.3734, www.vcnet.com/measures. end -- FAQ on WWW: http://www.contesting.
/\ Nor did I Steve - provided that the earth/ground for the tuner is separate from all other grounds. cheers - R. L. Measures, 805.386.3734, www.vcnet.com/measures. end -- FAQ on WWW: http://www.con
That's how tuners are supposed to be built, with one possible exception. I don't know what that exact circuit is, but moving the balun to the input of the tuner does NOT help balance, or make the ba
One of the simplest, practical, and cost-effective solutions to those who use open feeder/ladder line with multi-band antennas is the approach re-introduced by Cecil, W6RCA. Cecil has been an advoca
I take offense to this comment since I posted the original message. 1.) You have no idea what my dipole looks like. For your information it is a dipole with multiple lengths of wire cut for different
Well, my problem was that my capacitance on my old tuner was pretty much maxed out. I couldn't add more. Believe me, I remember our conversation. But when the cap is fully meshed when it arcs, there'
For those of you interested in manufactured tuners check out March 97 QST or their web site for reviews of 4 legal limit tuners. High end and low end are represented. Power handling, loss, heating, a
I had a similar experience to Jon's with trying to tune an 80 meter delta on 75 meters using an MFJ989C. The tuner arced very badly at even moderate power levels, so I pulled the top cover off to see
/\ /chortle/ /\ Perhaps you should have done your homework beforehand, Mr. Rauch. The circuit used in the *Balanced* Balanced tuner is a balanced L-network -- invented in the 1930s by Bell Labs. No
/\ Yea, verily. /\ Operating coax at high SWRs is undoubtedly an engineering faux pas. However, open wire line would work just fine /\ are the wires less than 60º apart? another /\ There's alwa
In a series circuit, lower C, and larger L implies higher Q. The capacitors in a T network are in series, and thus see a voltage drop that is equal to something like Vin/Rin*Xcin = Vin * Xcin/Rin = V
Unfortunately wider spacing increases voltage at the same rate as the wider spacing increases voltage rating when as you are using far less than optimum capacitance. You really gain nothing, for a c
FWIW, RSGB Radio Communication magazine a while back showed how the caps on a conventional T match could be made to operate simple shorting switches at the extreme end of their rotation, thereby conv
Hi all, You can learn a lot about how the T-tuner will operate using the simulator at this link: http://fermi.la.asu.edu/w9cf/tuner/tuner.html You will notice that the maximum power transfer efficien
Come off it, Rich, it's not semi obvious. It's standing-there-shouting-glaring-one-in-the-face obvious! Even with ferrite baluns, it works - and extremely well, too. The technique has been around a l
Here we definitely agree. Starting from the R + jX you need to match, a dedicated tuner can be designed to have the lowest operating Q for a particular impedance transformation ratio. Just how well b