A Co-Phasing Harness is used if you want to use 2 CB Aerials on a single CB radio.
Made with equal length 75 Ohm RG-59 to Maintain a 50 Ohm impedance to the radio.
INCREASE RANGE UP AND DOWN THE ROAD
You’ve likely heard that dual antennas will increase your transmit and receive range. and this is partially true. as long as you’re talking to people either directly in front of or beyond your vehicle.
Assuming no obstructions. a single CB antenna has a uniform. circular signal pattern. It can send and receive in all directions equally. as illustrated by the picture below.
Dual antenna installations don’t have the same signal pattern. Instead of being perfectly circular. their pattern is much more oval shaped – with the oval being stretched in the direction of travel.
So with a dual CB antenna setup. you’ll be able to talk further up and down the direction of travel – which usually works out well given the direction of most roads. But you do lose a bit of range to the right and left side. which isn’t ideal for all circumstances / drivers.