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Im Interested in building a Bi Square antenna. I've done extensive research both on the internet and my bookself and via Cebik/ARRL and others Im getting conflicting information. Some say each leg is 1/2wavelength long, others say each leg is 1 wavelength long.????? (1 leg: been from the feed point to the wire end at the top of the diamomd) Ive check'd and double checked and the sources still conflict, maybe could someone please post the "definitive and correct design spec"  for this antenna..........
I would be most grateful

Joe Carrs book says 1/2 wave per side for total wire length of 2 wavelengths.
Glen WT0A

Allen C. Ward:
Note that a halfwave per side equals one wavelength per leg, i.e. there are four sides and only two legs.

Tom Rauch:
I've had bisquares and a friend used a few also.

As a matter of fact just the other day I was modelling a bisquare array for 80 meters.

The bisquare is similar to a Lazy H antenna except the open ends are closed and one feedline is omitted and that port left open.

Both antennas are generally colinear and broadside combinations. They are two half waves in phase stacked over two more half waves in phase. Now the Lazy H does not need to be two half waves in phase, the elements can be longer or shorter, but the bisquare ALWAYS has to be two half waves in each stack to have the correct pattern.

The disadvantage of the bisquare is slightly reduced gain and single band operation. The Lazy H can work over a nearly 3:1 frequency range, the bisquare is single band for a good pattern.

The bisquare is 1/2 wave on each of the four sides. It is two waves around the entire loop and is open opposite the feedpoint, although if broken and fed Lazy H style it will cover two bands with a broadside pattern.

If you only had a 1/4 wave on each side of the square the pattern would be off the sides and with a 90 degree polarization shift. Of course if you shorted it at the open end it would be a quad loop, be broadside, but hardly have any gain over a dipole.

To have useful gain over a dipole it has to be 1/2 wave per side, or 2 waves total around.

73 Tom

Mike Brenza:
Tom is right on!
And, after you try that bisquare, consider the "Lazy-H" he mentioned... it is a great antenna!



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