I've found somethng interesting

[G4LNA]

I normally use a 30Mtr square loop because of space restrictions in my garden. The other day I decided to change the shape of the loop and extend the lower leg like in the first picture.

When I first modelled the square loop, as you would expect it was a pretty good cloud warmer on all bands, but since extending the lower leg its all gone vertical and on most bands the radiation angle has come down markedly, except 21MHz which is pretty rubbish. I have noticed that I'm working the USA quite regularly on 7MHz in the mornings now.

I do feed the antenna with open wire line to a home made matching unit, so the funny impedances do worry me too much.

I just put this on in case it is of use to someone else that has space restrictions.

I'll put the remainder of the polar diagrams for the other bands on a second post.

[G4LNA]

Here is the remainder of the polar diagrams.