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Reviews Categories | Antenna parts, accessories, incl. baluns, hardware, etc. | BALUN DESIGNS Dual Core 4:1 Current Balun 5kw Teflon #4115 Help

Reviews Summary for BALUN DESIGNS Dual Core 4:1 Current Balun 5kw Teflon #4115
BALUN DESIGNS Dual Core 4:1 Current Balun 5kw Teflon #4115 Reviews: 17 Average rating: 5.0/5 MSRP: $97.95
Description: For the ham that wants the ultimate 4:1 current balun, this new dual core design fills the need! This is a balun originally designed by Guanella and subsequently improved by Dr. Jerry Sevick (W2FMI). By utilizing Thermaleze wire inserted in teflon tubes, Dr. Sevick was able to substantially increase the breakdown voltage between both conductors and windings while improving the overall input impedance. Building the balun with two separately wound cores (one for each conductor) creates 5kw of total power handling (10kw PEP) and greatly increases the inductive reactance.

Product is in production.
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WD9CMD Rating: 5/5 May 25, 2009 12:07 Send this review to a friend
Excellent Product  Time owned: 3 to 6 months
I purchased this balun in the OCF version to give a try to an off center fed dipole. The results were better than expected. The balun is a very high quality product. Since I run an amplifier quite often, I wanted a balun that will take the high rf and live a long life. This balun is the ticket!! Bob is excellent to deal with and very fast shipping. A credit to amateur radio.
73's, David
W0BUW Rating: 5/5 Feb 28, 2009 08:50 Send this review to a friend
Best torroid design to date.  Time owned: 0 to 3 months
I have been designing and using air baluns since 1949. I have been able to make air baluns, that function on all the ham bands with great success. There are many Balun designs for sale on the internet. I just purchased a model 4115T to be used at high power on my V Beam to Europe. The reason I previously stayed away from Torroid Baluns is the fact that they saturate at high power and degrade there use rapidly. Bob, KZ5R has designed a high power torroid balun that, because of the permability factor is an ideal core for our frequencies.I have conducted detailed tests on my dual scope and his balun is one of the best balanced I have tested to date.
The quality of this balun is perfect. The best hign power 4:1 current balun to date. Buy it with confidence.
Boyd, W0BUW
SV2BWM Rating: 5/5 Dec 24, 2008 11:34 Send this review to a friend
Recommended!  Time owned: 6 to 12 months
I have this balun with a vertical mast 7.8m and some ground radials. This antenna tunes very easy from 80m to 6m with the help of LDG-1000. Reports are very good for such a simple antenna...
WC4R Rating: 5/5 Dec 22, 2008 09:32 Send this review to a friend
The best of the best  Time owned: 0 to 3 months
OMG!!! This balun is amazing. Perfect in every way.
I bought the eyelet version to replace my Radio Works burnt balun on my super loop. What a great upgrade. A week later I got the stud version when I built a 160m flat-top fed with ladder line.
Bob is fantastic to work with; fast email and telephone response. Quality on top of quality. No sealed up with epoxy unit here either. Bob designed it so you can take a look inside and inspect his workmanship. His web site shows honest interior pictures of the product build.
VERY reasonable price considering what you actually get. These products will really handle high power AND high SWR. THE BALUN for the real world. After 35 years I finally found a balun that will go on every one of my antennas.
W6IZT Rating: 5/5 Dec 16, 2008 08:35 Send this review to a friend
A great product  Time owned: 0 to 3 months
I purchased this balun to use with a Nye Viking MB-V-A tuner. I was experiencing noticable current imbalance with the internal 1:1 balun. I normally wind my own baluns but I thought that I would give this one a try.

I am very impressed with the overall quality of the balun. With this balun I am not longer seeing a current imbalance.

Well worth the price

K2VI Rating: 5/5 Dec 3, 2008 16:42 Send this review to a friend
commercial grade  Time owned: 6 to 12 months
Im one critical person and it take's quite a bit to impress me, I must say i have never seen such an extreme duty balun in all my days as a ham operator. I smoked many baluns but this 4:1 dual core balun is impervious to RF damage. I might add that bob is a great person to deal with and will always offer suggestions to make your antenna preform to it's optimum ability.Bob is highly knowledgable and friendly.As a side note, I just ordered another dual core balun just in case bob decides to retire. It will probably never be used but good insurance,As of this time there is no balun as efficient and strong as bob's balun designs baluns.Thanks bob.
tony K2VI
AE4CW Rating: 5/5 Aug 16, 2008 15:07 Send this review to a friend
Excellent 4:1 Balun with Great Common Mode Choking  Time owned: 0 to 3 months
This is Dr. Sevick's premiere 4:1 current balun design. It's transmission lines are wound on two separate ferrites with twice the number of turns that are possible on a single-core design. This results in a major increase in common mode impedance across the HF bands.

I asked Bob (the owner) to build this version to see how well it could handle the high common-mode RF levels I was seeing on the coax coming into the shack from my OCF dipole with a single-core balun. In a word the results were EXCELLENT.

On 40M through 6M common mode currents were reduced by a MINIMUM of 15X (yes, 15 times less RF on the outside shield of the coax). The 80M reduction was about 2.4X, so an additional common mode choke might be necessary, but not so far. The by-product is that the antenna is now being fed with almost all the transmitter power rather than radiating from the transmission line or being shunted to ground.

So, if you need a 4:1 balun that can handle tough situations, this is likely the best one you can buy anywhere.

P.S. Balun Designs also has a single-core 4:1 balun paired with a 1:1 choke (model #4113ocf) which should yield similar results based on my experiments.
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