Sunday 21 April 2019

A little 6m work.

Well, it's not much, but it works fine enough.  The wire length was 1.37m per side for a SWR of just under 1.2:1.  Not that there was much to work - only Ireland and the Isle of Man today, with one PA station heard in rapidly changing, brief Es.

A multi-element beam and mast is on the list...


This is the HFTA gain prediction for the simple dipole, together with the terrain profile to the east.  Note the deleterious effect of the higher ground between me and the sea on low angle radiation:

At 4m above very good ground, the pattern, which is almost entirely horizontal radiation (blue), as you'd expect, is plotted below. MMANA-GAL reaches much the same conclusion about peak gain as the HFTA model does.  More height is needed, but it's fine for casual working, not least because 6m propagation is often binary: it's either strong or dead!


3 comments:

PE4BAS, Bas said...

Hello John, looks like a cloudburner to me. I think height will improve everything dramatically. Although you never know, ES propagation can be on very high angles as well. 73, Bas

Photon said...

Not quite a 'cloud warmer', but it was a 'get going this afternoon' job! The peak gain of +7dBi occurs at 22 degrees. If you stretch out your fingers and place your thumb on the horizon with an outstretched hand, your little finger will be at about 25 degrees. That's quite low, and there's useful gain below that. Gain is also relative, and doesn't mean a contact can't be made, even in the negative territory.

PE4BAS, Bas said...

I absolutely agree with you. Although people tend to talk about DX antennas should have a low radiation angle. That doesn't mean you can't DX with a antenna that has best radiation on high angles. Especially for ES-propagation I think it is not that important. I dismantled my radiating tower setup yesterday since some of the radials were in the garden and everything is growing again now. My XYL doesn't find it a nice looking thing anyway. Next year I'll try a sloper configuration just for 60m fed at top of the tower like you use for some bands. 73, Bas