Years ago, I did that with two HyTowers and the 4 sq box from Comtek if I
remember correctly. It worked okay. Give it a try. 73 and good luck! Rod/w7zrc
From: Matt <maflukey@gmail.com>
To: towertalk@contesting.com
Sent: Tuesday, November 29, 2016 8:57 PM
Subject: [TowerTalk] FW: 2 Element phased vertical array using Comtek
Foursquare Box
The Comtek model ACB-4-A series units could be used to drive a 2 element phased
array by connecting the 2 verticals separated by a quarter wavelength on ports
#1 and #4 of the hybrid quadrature unit. Leave ports #2 & #3 disconnected but
do connect a 50 ohm dummy load to the dump port. You will need to feed the
antennas with 1/4 wave electrical length 50 ohm coax instead of the 75 ohm used
in the 4-square configuration - no impedance transformation is required because
only one antenna will be driven from the opposing sides of the hybrid bridge.
You may also want to call Dx Engineering or Comtek and just confirm this info
is still valid with the current series units but as far as I know it's
essentially the same circuit.
Hope this info is helpful. Good luck on you project.
73
Matt
KM5VI
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Marty s
Sent: Monday, November 28, 2016 1:27 PM
To: towertalk@contesting.com
Subject: [TowerTalk] 2 Element phased vertical array using Comtek Foursquare Box
Greetings Everyone.... hope CQ WW CW treated you well,
I have everything I need to erect a 40m foursquare on my tiny urban lot in MA.
It looks like I won't get it properly finished in time for this winter, but
would like to at least get some gain out of the two verticals I have up right
now, to get 2 directions of endfire. Can a normal Comtek box with no
modification be used to handle this, or is it more effective for me to just
phase the two verticals with a homebrew box relying on 1/4 wave 75ohm phasing
lines?
Thoughts, opinions, concerns, questions?
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|