[TowerTalk] Two 15M stacking

Stan Stockton k5go at cox.net
Sat Feb 24 23:45:37 EST 2007


Check the results in my link above
versus other MMs using much larger systems...I don't
think you will find their much larger antennas
make a significant difference.

Obviously you have a good antenna system on 10M but (the real compliment follows, Bill) in my opinion the VAST majority of the reason for your results or anyone else's results is the operating ability as opposed to the effectiveness of their antenna system.

You originally said:

My 6 element KLM array has a 3 dB beamwidth of about 54 degrees, which is plenty for Europe.

There was dispute from K1TTT, I think, who said that more than 4 or 5 elements was too narrow from the East Coast for Europe.  My example was to add food for thought regarding a higher gain antenna and just how many degrees off you have to be to have a weaker signal than with the original antenna.   

In my example I said suppose you doubled the boomlength and achieved another 3 dB which would narrow the beamwidth.  Doesn't matter it's a little 4 element 15M Yagi on a 24 foot boom or what.  My point was, that in order to compare two antennas to know whether you could possibly lose anything because of the narrow beamwidth, you would have to look at the 3 dB beamwidth of the one with X gain and then compare it to the 6 dB beamwidth of one with X + 3 dB of gain.  I have seen some compare the - 3 dB points and say, for example, that because the 3 dB beamwidth narrowed by 20 degrees that it is too narrow not realizing that they would still be nearly as strong at the original beamwidth with the additional gain of the larger antenna.  

I'll still take all the gain I can get pointed at DL.

Stan, K5GO

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