Max stacking gain for dipoles is 5/8 wavelength. Max stacking gain for yagis
varies with boom length. For the 6m7JHV with a 30ft 8in boom length, stacking
distance will be in the 25 to 26ft range. As always, before cutting and
drilling the stacking should be confirmed by one of the yagi modelling programs.
You can stack closer but the maximum realizable stacking gain will not be
reached. In this case, you could be better off with a single longer yagi than
understacked yagis. If the stacking is wider than optimum, the gain doesn't
suffer but the main lobe becomes skinnier and other grating lobes become higher
in
amplitude.
73/k5gw
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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