just to be sure if you have an ohm meter connect one side to the outor antenna ring or chassis mounting hole then touch the other end to both power pins. The one that reads zero ohms is ground.
--- On Fri, 1/1/10, Joe <k1ike_m...@snet.net> wrote: From: Joe <k1ike_m...@snet.net> Subject: Re: [Repeater-Builder] Motorola R1225 to GR400 conversion questions To: Repeater-Builder@yahoogroups.com Date: Friday, January 1, 2010, 9:20 PM Eric Wolf wrote: > 1) The sale did not include a power supply, thus I am using an Astron. > Because everything was disconnected when I got it, I have no idea > about the power wiring scheme. Be VERY careful connecting Dc power to the back of the radio. The power plug is not marked as to polarity, but I believe that the pin closest to the center of the radio is the positive and the pin closest to the side of the radio is the negative. Verify this. The type of connector used is similar to what older CB sets used to use and they are available a Radio shack. Radio Shack sells a double ended cable, be absolutely sure that you use the correct end if you get one of these cables. 73, Joe, K1ike