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Delta 2000


M0GVZ

Sr. Member
Oct 18, 2011
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Using a larger diameter wire up the middle of it would make it more broadband without impacting efficiency. So if they chose to use braid instead of the thin solid wire that the Imax and A99 use that would make it more broadbanded on the band it's designed to work on.

Multi-band coverage though, like the 15-10m the Imax can do depends on the matching section HOWEVER the Imax and A99 aren't actually true multiband antennas rather the values of resistance and reactance the matching sections produce on those bands result in a SWR that's within a usable range.
 
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M0GVZ

Sr. Member
Oct 18, 2011
1,771
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I'll stick to the Imax 2 K working from 18/15/12/11/10 meters.

better as a multiband ham antenna with lossy traps.

No it isn't. It works as a multi-band antenna because of significant losses both in the matching section and your coax outside the 10/11m band. Traps in antennas like the Hustler BTV series have very low loss ,hundredths of a dB.
 

Justme

Sr. Member
Jan 28, 2008
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The Netherlands
At 15 it is an high impedance 1/2 wave antenna so the matching network does fine.
Coax used better as LMR 400 SWR on 15 1:1.3.
Working every continent there so if it was a leaky dummy load there explain please why it works as good or better as my Fritzel FD-4 at 40 feet up also fed with better as LMR 400 Coax.
The only difference i see is polarisation differences, sometimes the FD-4 wins sometime the Imax 2 K wins.
Even on 18 MHz it works decent though there it needs the tuner for the swr is 1: 2.3.
Same as 15 meter the FD-4 wins sometimes, sometimes the Imax 2 K wins.

If i would have large losses using 1000 watts into it which i did over longer qso's it would have burned out the matching system on any of the bands used.
losses of an trap are about 0.5 dB add several traps if you work with a multiband vertical trap antenna.
Don't forget trap losses add up in multiband verticals...
and mostly have a much narrower bandwidth.
Traps also form a weak point in the antenna and need decent weatherproofing all the Imax 2 K does not need bar the antenna plug.

So for 10/11 and 12 meter i have an full 5/8 antenna on 15 and 18 an 1/2 wave antenna.
Every trap antenna uses 1/4 wave sections for the bands, traps with losses to couple the next section for the lower band etc.
Even on 18 where the swr is a bit off with low loss coax i have relative low losses with a good tuner.
on 15 where the system is good almost no losses.
As on 12/11/10.
I don't work 11 bar the 1 x a year saying hello to a good friend there.
So, with all due respect i don't go with your observation.
 
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