noise canceling Elevator /HF?
hi
I've had some interference from 1 to 30 caused by new elevator
equipment.
my building lookes like a long but narrow rectangle
it's about (rounding off) 100ft long maybe 50ft wide i'd guess
on each far end of the rectangle is an elevator room
both throw out same type noise
my antenna a horiz dipole center tuned (SGC) is ontop of the Eastern
one
some have recomended to help cancel the noise i try a noise
canceling device like a timewave anc4(others are simular so i'll use
anc4 as example)
i happened to have one hooked up anyway and already had a small
antenna extra up there i taped to the side of the elevator room it
picks up noise fantastic
the anc never really seemed to fix the noise i am really trying to
kill thou i will say over all in general every now and then some
noise (not by my building) can really be cancled by it when it
works it's great but it works so poorly for my situation*(not the
above elevator noise) but the other far an few randum noise i wouldnt
recomend one unless you specifically know it can help your specific
instance
sorry to a side track but it leads me to so why didn't this kill my
noise
(lets forget about that 2nd elevator for a second)
so turns out these things are designed to 'null' noise a)further away
than both your main antenna and noise antenna and b) presumes you can
sepereate the noise antenna from main ant.
i sorta understood 'b' didn't know about a
further the 2nd elevator is about 80 feet i can't tell if the
noise from it is getting over to the other side/elevator where my
antenna is aka east side if it is i realize my question below
becomes very complex
so question
how does one design a device ie what kind and whom can design
essentially a anc4 like device that can create a null in the
situation i have lets assume the 2nd elevator is not causing me
issues
not even sure the theory behind it, i sorta understand how the anc 4
works thou
anyone have any ideas? any partial or total null could really help
me out if it's poss to create one w/o sacrficing my rx sensitivity
overall too much
|