Connecting a CAT controller to a Kenwood TKR-720 or TKR-820 Repeater can be accomplished easily by following these steps.

Build a interconnect cable with a DB-25 male connector on one end and a 15 pin Molex connector on the other end. (Note: a pre-built cable can be special ordered from CAT).

Note: Install a 2200 ohm pull-up resistor on the controller board at the COR #1 position. Set dip-switch #1 to the ON position for an active low COR.

Connector is a male Molex catalog #1625-15PRT (.062 inch pin spacing)