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Rob is on the right track. You need 75 ohm coax for the phasing harness. The length depends on what you are trying to accomplish. A typical trucker setup that is installed so the antennas are on either side of the cab is usually trying to accomplish an elliptical signal pattern: one that is stronger to the front and rear but still has some signal to the sides. To do that, you need to feed each antenna with a length of coax that is an odd quarter wave multiple: 1/4 wave, 3/4 wave, 5/4 wave, or something similar. For the typical mobile/truck install, that's going to be either 6 feet (1/4 wave) or 18 feet (3/4 wave) depending on the length. You can run both cables directly into the PL-259 and connect that to your radio.

Keep in mind that you can sort of direct the signal the way you want to with a cophase setup if you have the antennas spaced properly. Let us know what you're trying to accomplish and we can give you more precise advice.

<blockquote data-quote="Moleculo" data-source="post: 148918" data-attributes="member: 1">Rob is on the right track.&nbsp; You need 75 ohm coax for the phasing harness.&nbsp; The length depends on what you are trying to accomplish.&nbsp; A typical trucker setup that is installed so the antennas are on either side of the cab is usually trying to accomplish an elliptical signal pattern:&nbsp; one that is stronger to the front and rear but still has some signal to the sides.&nbsp; To do that, you need to feed each antenna with a length of coax that is an odd quarter wave multiple:&nbsp; 1/4 wave, 3/4 wave, 5/4 wave, or something similar.&nbsp; For the typical mobile/truck install, that&#039;s going to be either 6 feet (1/4 wave) or 18 feet (3/4 wave) depending on the length.&nbsp; You can run both cables directly into the PL-259 and connect that to your radio.&nbsp; &nbsp;Keep in mind that you can sort of direct the signal the way you want to with a cophase setup if you have the antennas spaced properly.&nbsp; Let us know what you&#039;re trying to accomplish and we can give you more precise advice.</blockquote>

[QUOTE="Moleculo, post: 148918, member: 1"] Rob is on the right track. You need 75 ohm coax for the phasing harness. The length depends on what you are trying to accomplish. A typical trucker setup that is installed so the antennas are on either side of the cab is usually trying to accomplish an elliptical signal pattern: one that is stronger to the front and rear but still has some signal to the sides. To do that, you need to feed each antenna with a length of coax that is an odd quarter wave multiple: 1/4 wave, 3/4 wave, 5/4 wave, or something similar. For the typical mobile/truck install, that's going to be either 6 feet (1/4 wave) or 18 feet (3/4 wave) depending on the length. You can run both cables directly into the PL-259 and connect that to your radio. Keep in mind that you can sort of direct the signal the way you want to with a cophase setup [I]if[/I] you have the antennas spaced properly. Let us know what you're trying to accomplish and we can give you more precise advice. [/QUOTE]

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