ive decided to wind my own 4:1 current. i use one from mfj right now and it works, but i want to wind my own. holy crap the differences in cores. 31 or 17 or 43.............im using an ocfd that covers 80-6 with very acceptable swr so i dont need to use a tuner. which is what i wanted. but which core is best for this?
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4:1 current balun
- Thread starter nfsus
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How to Buuild a 4:1 Current Balun - by KB1LQC
Learn how to build a 4:1 current balun. Plans, parts list and pictures by Bryce Sali- KB1LQC. A fun project and easy to build!
hamuniverse.com
Mix 31 - Off Center Fed (OCF) Antennas - Palomar Engineers®
palomar-engineers.com
50:200 ohm (4:1) Dual Core Current Balun Kit, 1-55 MHz, 1500 watts PEP, for OCF, Loop, Ladder Line Antennas - Off Center Fed (OCF) Antennas - Palomar Engineers®
Purpose. Model BA-4-1500DC is a 4:1 dual core balun kit (assembly required from parts supplied) used to translate a 50 ohm input up to 200 ohms at RF power levels up to 1000 watts when used with a matched load. It provides conversion from unbalanced coax to balanced ladder line/antenna feed...
palomar-engineers.com
Since you also want to use that OCF on 6 meters i would prefer 43 mix.
31 would work on 160 as well at cost of efficiency at 10 and 6 meters.
current baluns need 2 cores, single core don't work so well.
31 would work on 160 as well at cost of efficiency at 10 and 6 meters.
current baluns need 2 cores, single core don't work so well.
In the 11m band. I followed the instructions from Steve, Karima’s page.
That is a totally different beast than a 4:1 balun.
Yes, Forest Runner you are using a core as a choke.
What they are talking about here is winding two individual wires in different numbers of turns around the core and making a transformer.
Some antennas do not present a 50 ohm load, but that's what your radio wants to see.
They transform a high impedance load down closer to 50 ohms.
73
Jeff
I use a 4:1 Coaxial balun on my 80 Meter Loop. Is a low power (probably rated 800 watts or less) cheapie purchased from HRO like 30 years ago for under $25. Have carried around and used on Loops at 4 different places I have lived at in that time. Still in service.
I used my ear. LOL Seemed like noise dropped more. I also went with Steve K’s updated graph and he also had better numbers with the type 61 mix.
Edit: I also used my VNA and its numbers looked better and also the smith chart was looking good!
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