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Old November 6th 04, 08:49 PM
John Smith
 
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"Silvio" wrote in message
...
hi..........
please need help with delta loop antenna better matching system than gamma
match............. please could any body sugest any thing or way to match
a
vee quad , dela loop other than gamma match and my be supply me with
details
how to assemble and fit to antenna .........gee some must no a better
way..
please help me 73s .......... thanks every one that may be
able
to help .............



Hi, Silvio -

I am not very good at antennas and such, but I'll give it a shot.

EZNEC says a delta loop fed at the vertex (at the bottom) appears as about
122 Ohms at resonance. You could use a 1:1 balun and a quarter wave piece of
75 Ohm coax and then 50 Ohm coax for the remainder of the trip to your
transmitter. At the 75/50 Ohm point your impedance would appear as 46 Ohms.
This would give you an SWR of about 1.08:1.

If you do not have 75 Ohm coax, you could instead insert an open stub of
about .381 wavelengths at about .159 wavelengths below the balun using all
50 Ohm coax.

And then there is the possibility of using open wire line with a tuner.

Hopefully, I did all this correctly. If not, I hope someone else will jump
in here and correct me.

Good luck.

John