[CQ-Contest] Two Towers, Two Tribanders - Coax Length for Stack Match?
n2icarrl at gmail.com
Sun Jul 12 23:30:07 EDT 2015
Ah, the unidentified "others" who don't identify themselves.
As long as the two antennas are pointed in very different directions, so
that the gain in the two directions is very different, there is no
reason the be concerned about phase differences. To illustrate,
vectorial add two signal sources, one of which is 10 dB greater than the
other. How does the net power change as the phase angle of one signal
source is varied with respect to the other signal source ? Very, very
little. KK9A is correct.
On 07/12/2015 12:04 PM, Charles Harpole wrote:
> I have been told by others that KK9A is wrong and that having two different
> coax lengths will present different impedance and different phase to the
> different antennas, in some case being lucky and ok with some lengths and
> some other messing it all up.
> tnx, Charly K4VUD
> On Sun, Jul 12, 2015 at 11:29 PM, <john at kk9a.com> wrote:
>> If the towers are being used for spraying in different directions there is
>> no need to equal length coax.
>> John KK9A
>> To: CQ-Contest at contesting.com
>> Subject: [CQ-Contest] Two Towers, Two Tribanders - Coax
>> for Stack Match?
>> From: Richard Thorne <rthorne at rthorne.net>
>> Date: Sun, 12 Jul 2015 07:14:07 -0500
>> I'm in the process of putting up a second tower which will have stacked
>> tribanders. These 3 tribanders will be fed via a Stack Match with equal
>> lengths of coax.
>> My current tower also has a tribander.
>> I plan on installing a stackmatch II switch between the two towers for
>> direction changing or spraying my signal in 2 directions.
>> Is it worth the trouble to use equal length feed lines? If I use what I
>> currently have one feed line will be 278' and the other will be 140'.
>> Rich - N5ZC
>> CQ-Contest mailing list
>> CQ-Contest at contesting.com
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