On 11/5/16 10:09 AM, Mike Smith VE9AA wrote:
WL (Wilson Lamb)....callsign?
Imagine one 4-square.....now imagine another 4-square beside it.(perhaps
5/8wl away).....now imagine another beside that one.......and a 4th.
16 elements in all..Four 4-squares in all.
All these 4 squares are in a "line" going (roughly) from the NW to the
SE.....so, in my mind, the 16element array (if I built it that large) would
(probably) be best to the NE and SW as all arrays will see the same
wavefront in those 2 prime directions from here in NB..just NE of the State
of Maine.
The arrangement of the 4 square "sub-arrays" might not need to be in a
line, whether broadside (your description) or endfire to your desired
directions. It affects the (relatively simple) phasing network you use
to divide the power among the arrays.
if they're broadside, then it's really easy: drive them all in phase.
But if they're end-fire (as an example), if they're spaced right, you
could probably also drive them all inphase (or maybe 180 degrees out,
which is just as easy).
It's a single band system you're thinking about, so even a more complex
phasing can be done with just the right lengths of coax. Getting the
phasing "wrong" by a bit doesn't have a big effect on forward gain (30
degrees error is less than 1 dB). It would affect your null depth for
F/B, but you're getting your null depth from the 4 squares, so the feed
network to the sub-arrays isn't as critical.
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