20 meter dipole (with or without a balun) ?

[WALTERB]

I believe I should be using a balun (4:1) for my dipole which is fed with RG-213.

Would it work better without a balun?

thanks

[W0BTU]

If it's a half-wave dipole, why would you use a 4:1 balun with coax? You would only use a 4:1 balun to match an impedance that's ~4 times higher or lower.

What you want is a good current choke, which is effectively a 1:1 balun. It will keep undesired currents off the coax shield, and keep the shield from picking up RFI.

I highly recommend that you read the excellent material on baluns and chokes on K9YC's site at http://audiosystemsgroup.com/publish.htm.

[WX7G]

If you use a balun with 50 ohm coaxial cable the balun should be a 1:1 current balun. Otherwise feed it without a balun.

[WALTERB]

If it's a half-wave dipole, why would you use a 4:1 balun with coax? You would only use a 4:1 balun to match an impedance that's ~4 times higher or lower.

What you want is a good current choke, which is effectively a 1:1 balun. It will keep undesired currents off the coax shield, and keep the shield from picking up RFI.

I highly recommend that you read the excellent material on baluns and chokes on K9YC's site at http://audiosystemsgroup.com/publish.htm.

Yes, it would be a half wave dipole with each leg about 16.5 feet long.

thanks

[WALTERB]

actually it will be fed with RG-8X.  I decided since its such a short run (< 50 feet).

[WB6BYU]

The SWR will be higher if you use a 4 : 1 balun than if you feed it directly.  That's because
the dipole impedance is close to 50 ohms, and a 4 : 1 balun is designed to match 200 ohms.

Use a 1 : 1 current balun if you are going to use anything.

The dipole may work just fine without a balun, depending on a  number of factors including
the length of the coax and what else is connected to the coax shield at the station.  And
performance can shift if there are any changes.  A balun makes behavior more predictable.  It
isn't required - don't let the lack of a balun keep you from getting on the air - but it increases
your chances that the antenna will work properly without adverse effects.

[WA8UEG]

Have used 1/2 wave dipoles fed with 52 ohm coax since 1964, never used a balun never had an issue.

[WALTERB]

ok, thanks to all!