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  4sqRelayCntrl.JPG - Here's the control box.  The direction of the array is selected by sending positive, negative or both(AC) current to the phase box via the RX coax.  I have added the ability to control the direction with digital inputs.  Thats the function of the transistors.  If you want to add a pre-amp at the array this might be a problem.  In that case run a control cable directly.  In my application I have 850' of RG-6 between the rig and antenna.  I use a pre-amp at the rig to improve it's noise figure.  On 160 in the middle of the day when the band is quietest I get a 13db rise in the noise floor when switching from the dummy load to the array.  Therefor, adding a pre-amp at the array would be a waste and probably generate BCI IMD.  Note, if you use digital control make sure the switch is left in the open position.  Here's the schematic:   4sq_console.pdf  
 
 
 
 
 

Here's the control box. The direction of the array is selected by sending positive, negative or both(AC) current to the phase box via the RX coax. I have added the ability to control the direction with digital inputs. Thats the function of the transistors. If you want to add a pre-amp at the array this might be a problem. In that case run a control cable directly. In my application I have 850' of RG-6 between the rig and antenna. I use a pre-amp at the rig to improve it's noise figure. On 160 in the middle of the day when the band is quietest I get a 13db rise in the noise floor when switching from the dummy load to the array. Therefor, adding a pre-amp at the array would be a waste and probably generate BCI IMD. Note, if you use digital control make sure the switch is left in the open position. Here's the schematic: 4sq_console.pdf Download Original Image
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