Probably a stupid question, but...
On 20 Sep, 22:39, Roy Lewallen wrote:
Trying to phase two antennas that close together at that frequency range
will be an educational experience at best, but more likely just an
exercise in frustration unless you have much more patience than average.
Such an array will be hyper-sensitive to everything. You might be able
to fleetingly see a null after a lot of tweaking, but I seriously doubt
you'll even get that. A tiny change in frequency, wiggling of the whips,
or even movement in the vicinity of the whips will have a profound
effect on any null you might see.
If a null from a small antenna is what you want, you'd have much better
luck with a carefully constructed and balanced ("shielded") loop.
Roy Lewallen, W7EL
If it was just for receiving I would make two antennas in coil fashion
as shown every where
on the net, connect them together with a half wave length coax and try
stretch them apart as much as room suplies and then roll the excess
phasing coax up. The cb's have the super scanner antenna that partialy
follows this principle using 1 wave length antennas with the
connecting coax folded and pushed inside the connecting aluminum
channel. Using a rolled antenna tesla style with them being physically
close together would be an interesting experiment. Look up in the net
home made radios for the station tuning method and also you might want
to choose different methods to connect them starting with a wire
connecting the two wound antennas at the top and feeding th bottom!
( that method by the way requires the two antennas to be wound
inopposite directions) I imagine you could get a null just like
turning an inside tv antenna because these stations in this
frequencyare high power as can be seen when a rogue station opens up
ontop of the station that you are listenning to and want to null out
of the picture.
Have fun
Art KB9MZ
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