using rg-58 for a balun

[p.larner]

can i make a 1-1 balun like this using rg-58?and an ft-240-43 torroid?.

[VK2AZT]

If you wanted to make an UNUN, go for it. You would be running the risk of the RG-58 crushing in on itself as the bending radius of the coax would be too small. Eventually the centre conductor would short to the braid but this would take quite a long time so don't worry about it. By using the coax you would make a nice common mode choke (CMC). This may work with your new antenna. Try it and see. It doesn't take long to wind one of these things.

Cheers.

[A.Z.]

yes

[Andy Chee]

Yes.

The picture you posted is commonly known as Reisert winding, designed to keep the input and output separated in order to minimise capacitance.

I use 12 windings of RG-58 (6 turns one side, 6 turns on the other) on a FT240-31 but #43 mix should be ok as well.

[A.Z.]

Yes.

The picture you posted is commonly known as Reisert winding, designed to keep the input and output separated in order to minimise capacitance.

I use 12 windings of RG-58 (6 turns one side, 6 turns on the other) on a FT240-31 but #43 mix should be ok as well.

I found that 17 turns (8+1+8) on a #43 result in a pretty good choke/balun over the 3.5...30 MHz range, willing to use higher power, the RG58 may be replaced by RG142, otherwise. using the RG58 and an FT240-43 core, the balun will be good for about 200W

[p.larner]

i know it will work as a common mode choke but will it transfer/match 300 ohm windowline to 50 ohm coax,ie work as a balun?.

[A.Z.]

i know it will work as a common mode choke but will it transfer/match 300 ohm windowline to 50 ohm coax,ie work as a balun?.

it will work as a BalUn, that is, it will BALANCE the currents so it will also avoid the insurgence of common mode currents; that said, 300 Ohm is the CHARACTERISTIC impedance of that window line, do you know what it means ?

[Andy Chee]

i know it will work as a common mode choke but will it transfer/match 300 ohm windowline to 50 ohm coax,ie work as a balun?.

Yes.  Here's more info:

https://www.dj0ip.de/balun-stuff/tuner-baluns/d-i-y-tuner-balun/

[A.Z.]

i know it will work as a common mode choke but will it transfer/match 300 ohm windowline to 50 ohm coax,ie work as a balun?.

Yes.  Here's more info:

https://www.dj0ip.de/balun-stuff/tuner-baluns/d-i-y-tuner-balun/

And then... given that the OP seems to be quite confused about baluns, or probably doesn't understand what a BalUn does, I'd suggest him to read the following

https://www.dj0ip.de/balun-stuff/balun-overview/

http://www.arrl.org/files/file/History/History%20of%20QST%20Volume%201%20-%20Technology/AntComp1-Lewallen(1).pdf

and then, stop for a split second and think; common mode currents are raised due to current imbalance, a BalUn purpose is to balance currents, so asking if a current BalUn like the one posted will act as a choke, means that one will need to stop and document a bit better about BalUns, and the above links may be of some help imVHo; then... there would also be to talk about BalUns and impedance transformers, the two aren't necessarily the same, and to add a bit more, the characteristic impedance of a given transmission line (say a 450 Ohm ladder line) has nothing to do with the impedance seen at one end of some length of such a line, when the other end is connected to a load presenting a composite impedance, and this sounds like the OP needs to further document about such topics