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Old December 31st 06, 01:57 AM posted to rec.radio.amateur.antenna
NomadW8 NomadW8 is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 6
Default Delta Loop Ideas Please

A full wave 20 meter delta loop, fed with open wire, ladder line or
even TV twin lead & a tuner will load up on all bands 10-40 meters.

Performance on 10-20 will be good, 30 & 40 a little less so.

Terry
W8EJO



John wrote:
I have been researching for a while now around the area of nested delta
loops. I want to upgrade my multi-band vertical antenna with delta loops,
each one resonant to cover 20 to 10m. However there is nothing on the
internet about nested delta loops. My wish is to have the delta loops
orientated such that they are pointed at the top and fed one third of the
way up one of the vertical sides to get a low angle of radiation.

I realise that they have an impedance of around 100 Ohms and this would need
to be matched. The usual method of doing this is to use a quarter wave
length of 75R coax to match to 50R.

Much in the same way that parallel dipoles can be fed with a common feeder,
can 5 delta loops be fed via coax matching stubs with a common 50R feeder?
(i.e. bring the ends of the matching stubs together?).

I tried in the summer to nest 5 delta loops with the feed point as described
above and then brought the feed points together (without matching stubs) ,
however it is not physically possible to do this - they really need
separating out.

Any ideas any one? My basic aim is to have 5 resonant antennas with no
tuning unit involved.

Thanks

John