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Why use s balanced tuner?
Why use a balanced tuner when a less expensive, easier to operate,
unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. |
Why use s balanced tuner?
Reg Edwards wrote:
Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. Because a balun particularly lossy at high SWR -- with a balanced tuner followed by a balun you present the balun with the correct impedance, so it's at its best. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Why use s balanced tuner?
"Tim Wescott" wrote in message ... Reg Edwards wrote: Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. Because a balun particularly lossy at high SWR -- with a balanced tuner followed by a balun you present the balun with the correct impedance, so it's at its best. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com ======================================== Tim! I don't know what design services you offer but you are WRONG. You must have been reading the wrong comical magazines. A choke balun is amongst the most power-efficient devices. It consists only of a pair of wires wound around a ferrite ring. It is just a very short transmission line of the same length as the wire and has the same very low loss. It has a phase shift of the same length of line. Which is immaterial insofar as the tuner is concerned. It merely changes the tuner L and C settings. ---- Reg. |
Why use s balanced tuner?
So a simple "pi filter" withe a bulun will do the same?
I always thought that the wide impedancerange of open wire made a currentbalun or voltagebalun unusable. I was just gathering parts to build my own balanced tuner.... Greetings Johan PE1AEQ "Reg Edwards" schreef in bericht ... Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. |
Why use s balanced tuner?
I don't know what design services you offer but you are WRONG. You must have been reading the wrong comical magazines. A choke balun is amongst the most power-efficient devices. I don't know where you get your balun information, but you really need to do more homework, apparently. BALUNs can become quite lossy, depending on the impedence characteristics of the antenna you are trying to match at a particular frequency. There are hundreds of sites where you can find this information.... http://www.cebik.com/a10/ant48.html is just one, for example. Do some homework. Ed K7AAT |
Why use s balanced tuner?
Reg Edwards wrote:
"Tim Wescott" wrote in message ... Reg Edwards wrote: Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. Because a balun particularly lossy at high SWR -- with a balanced tuner followed by a balun you present the balun with the correct impedance, so it's at its best. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com ======================================== Tim! I don't know what design services you offer but you are WRONG. You must have been reading the wrong comical magazines. A choke balun is amongst the most power-efficient devices. It consists only of a pair of wires wound around a ferrite ring. It is just a very short transmission line of the same length as the wire and has the same very low loss. It has a phase shift of the same length of line. Which is immaterial insofar as the tuner is concerned. It merely changes the tuner L and C settings. ---- Reg. Sorry. I thought you were asking for help. My mistake. Odd that you should answer the question when you already know the answer, though. To answer you unasked question: No, I do not have any test results, so you are correct that I am just repeating the absorbed wisdom of others. I'll be sure to qualify any similar answers I give in the future. Until I get an HF system up again I won't be doing any measurements, so don't hold your breath. To ask you the same question: would you please post _your_ test results? Pontificating from first principals is what you do if you are engaged in preliminary design or the unpaid answering of questions. Sticking to your guns in such cases is tilting over to philosophy, religion, incompetence or internet trolling. But you are sure enough of yourself to use capital letters when telling me I was mistaken, so you cannot possibly be incompetent or a spinner of trolls. So I am confident that you are working from real, measured data, not just derived results based on calculations or reasoning from first principals. At most you are once removed from some reliable individual or group who has done the measurements. It is very ungenerous of you not to share a properly detailed report on your experiments, or a reference to the report of the folks who did do the work -- a link to a page will do, or even a reference to a periodical or book should the information not be available on the web. I'm ready to change my thinking just as soon as I see something credible, and quite interested in the results because I don't see the point in building a balanced tuner if my existing unbalanced one will do. Thanks. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com |
Why use s balanced tuner?
On Mon, 2 Jan 2006 14:56:49 +0000 (UTC), "Reg Edwards"
wrote: Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. My link coupled tuner (Johnson Matchbox) cost me less than 60 USD, I can tuner faster than a T-type tuner, doesn't need nor use a balun. (Read one less component and its associated loss). So why would I want to replace it with something that works almost as good? Danny, K6MHE email: k6mheatarrldotnet http://www.k6mhe.com/ |
Why use s balanced tuner?
"johan aeq" wrote So a simple "pi filter" withe a bulun will do the same? I always thought that the wide impedancerange of open wire made a currentbalun or voltagebalun unusable. I was just gathering parts to build my own balanced tuner.... Greetings Johan PE1AEQ ========================================== All kinds of peculiar things can happen with voltage baluns and current baluns which have a definite impedance ratio. But my comments apply to a CHOKE balun, the most simple form of balun. It is a pair of wires wound together on a ferrite ring. It is just a very short 2-wire transmission line. For longitudinal currents it is an RF choke, the 2 wires being effectively connected in parallel. The impedances between which it can work are indeterminate. There is no impedance ratio. When connected between a balanced line and an unbalanced tuner, the tuner can be an ordinary simple L, Pi or T network. If you happen to have a balanced tuner, lying around doing nothing, then by all means use it without a balun. But if you don't have a balanced tuner, as is very likely, there's no need to make one. Just use a common or garden unbalanced tuner, which nearly everybody has already got, with a CHOKE balun. The hardest part of making a choke balun is obtaining the ferrite ring. 50mm outside diameter, 30mm inside diameter, permeability 200-400, about 16 turns of twin, flexible, stranded, speaker cable, will be OK for the HF bands. Or similar. All the very best for 2006. ---- Reg, G4FGQ. |
Why use s balanced tuner?
....[snip]....
The hardest part of making a choke balun is obtaining the ferrite ring.... Use a TV-set flyback transformer core; see: "another balun design", by Fred Brown, W6HPH, in Ham Radio magazine of May, 1982, pp. 54-57 "Three Baluns for a Buck" by Donald E. Lively, W6SJQ, from a magazine which didn't print either its name or the date on the pages I saved! but it basically says the same thing as the HR article. A hint on p. 37 of the August, 1987, QST describes "The Baby-Bottle Balun", an air-core balun based on DeMaw's article "Simple Coreless Baluns" (QST, Oct. 1980, p. 47; which I apparently didn't appreciate enough to keep). -- --Myron A. Calhoun. Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448 NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol) |
Why use s balanced tuner?
Tim!
I was out of order confusing your design services with baluns. Please accept my apologies. But I did make it clear that CHOKE baluns were involved. You may see elsewhere what a choke balun actually is. If you already have a balanced tuner then by all means use it. But if you don't have one there's no need to make one or buy one. It is more convenient to use an ordinary unbalanced tuner plus a very simple to make choke balun which has no particular impedance matching properties apart from being a very short length of transmission line of predictable Zo and predictable phase shift which don't matter very much. It seems my rhetorical question has inadvertently stirred up quite a discussion the newsgroup. I wish you much success with Wescott Design Services in 2006. ---- Reg, just a radio amateur, G4FGQ. |
Why use s balanced tuner?
On Tue, 3 Jan 2006 16:37:40 +0000 (UTC), "Reg Edwards"
wrote: Hi Reggie, It seems my rhetorical question has inadvertently Inadvertently? From you? Heaven forfend! stirred up quite a discussion the newsgroup. Aside from the grammatical error (missing preposition?) "quite a discussion" at a count of 9 (now 10) posts nearly half of which were you own? Old Son, you are the Donald Trump of rraa. [Don't worry, he's never written a bible of any sort.] 73's and Happy New Year Punchinello, Richard Clark, KB7QHC |
Why use s balanced tuner?
Dan Richardson wrote My link coupled tuner (Johnson Matchbox) cost me less than 60 USD, I can tuner faster than a T-type tuner, doesn't need nor use a balun. (Read one less component and its associated loss). So why would I want to replace it with something that works almost as good? Danny, K6MHE ========================================== Danny Boy, If you are happy with your link-coupled tuner, which can be either balanced or unbalanced, then by all means stick with it. I must admit it is something I forgot about. Many years back I had a similar commercial tuner. It didn't cover enough bands for me. So I dismantled it. The only parts worth recovering were the slow-motion variable capacitor drives and the nice skirted tuning knobs. Which I still have. They are of sentimental value. Ever since then I have used only home-brewed tuners with coils and capacitors connected with universal alligator clips. But never of the balanced variety. I wish you the very best of DX for 2006. ---- Reg, G4FGQ. |
Why use s balanced tuner?
Hi Richard (Clark)!
As usual you contribute nothing towards the technical knowledge of the readers. Who cares about them anyway? But I'm pleased you are still reading my stuff and am gratified to receive your seasonal greetings. May I, in return, wish You personally, Your Family and Friends, a Prosperous and Peaceful 2006. And while I'm about it, 2007, 2008, 2009 . . . . . ! ---- Yours, Punchinello |
Why use s balanced tuner?
Thanks Reg, i already have such a tuner but never thought it would be usful
with varying impedances. I hope 2006 will be good for you too... Greetings Johan PE1AEQ "Reg Edwards" schreef in bericht ... "johan aeq" wrote So a simple "pi filter" withe a bulun will do the same? I always thought that the wide impedancerange of open wire made a currentbalun or voltagebalun unusable. I was just gathering parts to build my own balanced tuner.... Greetings Johan PE1AEQ ========================================== All kinds of peculiar things can happen with voltage baluns and current baluns which have a definite impedance ratio. But my comments apply to a CHOKE balun, the most simple form of balun. It is a pair of wires wound together on a ferrite ring. It is just a very short 2-wire transmission line. For longitudinal currents it is an RF choke, the 2 wires being effectively connected in parallel. The impedances between which it can work are indeterminate. There is no impedance ratio. When connected between a balanced line and an unbalanced tuner, the tuner can be an ordinary simple L, Pi or T network. If you happen to have a balanced tuner, lying around doing nothing, then by all means use it without a balun. But if you don't have a balanced tuner, as is very likely, there's no need to make one. Just use a common or garden unbalanced tuner, which nearly everybody has already got, with a CHOKE balun. The hardest part of making a choke balun is obtaining the ferrite ring. 50mm outside diameter, 30mm inside diameter, permeability 200-400, about 16 turns of twin, flexible, stranded, speaker cable, will be OK for the HF bands. Or similar. All the very best for 2006. ---- Reg, G4FGQ. |
Why use s balanced tuner?
On Mon, 02 Jan 2006 10:20:30 -0800, Dan Richardson wrote:
On Mon, 2 Jan 2006 14:56:49 +0000 (UTC), "Reg Edwards" wrote: Why use a balanced tuner when a less expensive, easier to operate, unbalanced tuner, in conjunction with a simple choke-balun, will do just as well? Insert the 2-wire choke-balun between the unbalanced tuner and the balanced transmission line. ---- Reg. My link coupled tuner (Johnson Matchbox) cost me less than 60 USD, I can tuner faster than a T-type tuner, doesn't need nor use a balun. (Read one less component and its associated loss). So why would I want to replace it with something that works almost as good? I use my 500+ foot horizontal loop on 6 and 2 meters with homebrew balanced tuners from the '63 ARRL Handbook. On HF a balanced double-L tuner does the trick. The balanced-L tuner does use a balun but it is between the rig and the matching device. The only problem with using the Johnson Matchbox is 30M 73 de n4jvp Fritz |
Why use a balanced tuner?
Put a 500-pF variable capacitor in series with the link inside or, outside
the enclosure in series with the center conductor of the coax line feeding the JMBox. Gives you an extra degree of freedom in tuning. 73, Dave, N3HE SNIP between the rig and the matching device. The only problem with using the Johnson Matchbox is 30M 73 de n4jvp Fritz |
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