> Yuri, you're not reading the Stackmatch description carefully
> enough. The
> K8UR array is parasitic, and relies on a switchbox that
> disconnects all
> antennas except the one that is driven, and then uses the
> floating
> feedlines as inductive loads to make the undriven antennas
> appear as
> reflectors.
>
> As array solutions says, the stackmatch feeds the connected
> antennas
> in-phase, and their spacing would have to be adjusted to get
> directivity. The shields of all the feedlines are connected
> together
> through the case of the stackmatch, and so the K8UR-type
> behavior cannot be
> achieved with it.
>
> 73, Pete
>
OK, I can't tell the difference between the hammer and a screwdriver, now I
can't read :-)
"The three antennas are set up in a delta pattern or triangular pattern,
equidistant from each other. "
Can you enlighten me how to do that, while you are driving two elements in
phase, with third as a parasitic reflector, tuned by the coax, center
disconnected and shields connected? Or any other way how to use StackMatch to
feed 3 el vertical array in Delta configuration and using .41 phasing lines?
Also what is the difference between Delta and triangle pattern?
I said nothing about K8UR array.
What the Array Solutions is implying that you can use StackMatch to drive 3 el
vert array, either as one driven and two reflectors, or as two driven and one
reflector elements. I believed it, tried to set it up, only to find out it was
omnidirectional 3 el array, regardless how you switched it. Way back this was
rehashed on the reflector and some ON4 station had similar results and
diagnosed the problem to connected shields of feedlines. So in order for this
to work, it is necessary to insert the relays in the shield connections and
disconnect the shield for the unfed reflector element. Stack match instruction
should say that, otherwise it is false advertising, which I was one victim of.
I was excited about using SM for feeding 3 el. vert array, switchable to 6
directions, 160 - 10 m, but it is impossible without modifying it to disconnect
the shields from the box.
No such problems with Comtek and 4 square boxes, where all elements are force
fed.
73 Yuri, K3BU.us
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