The exposed pin closest to the heat sink is positive. The other pin that is in the plastic is negative.
Thank you that did the trick. I am new to the Motorola arena. Now that I know this I double checked it before applying power by seeing if the ground pin shorted to chassis ground and it does. I should have thought to check this before but I really appreciated the response. I might need to post a new thread but I have a follow up question regarding getting 4 wire audio? I have previously integrated a Tait TM9155 with an added audio line card to achieve the 600 ohm audio with a Trunked Analog Gateway by using this pinout:
Description TAG Pin Conn (HD15) Pins Description
E&M Signaling Input 1 <---------> 9 13.8V from Radio
E&M Signaling Input 2 <---------> 12 Busy/Gate
Audio Input 3 <---------> 4 4W_Line_In - (Audio Out)
Audio Input 4 <---------> 10 4W_Line_In - (Audio Out)
Audio Output 5 <---------> 14 4W_Line_Out - (Audio In)
Audio Output 6 <---------> 15 4W_Line_Out - (Audio In)
E&M Signaling Output 7 <---------> 3 PTT-IN
E&M Signaling Output 8 <---------> 7 GND
I am not sure where to get the same inputs and outputs from the MCS 2000 accessory Connector
Pinout for the Accessory Connector
1 SPKR+ 14 SW B+
2 INT SPKR+ 15 IGNITION
3 SPKR- 16 I/O 2
4 DIGITAL GND 17 LH RESET
5 BUSY 18 BUS-
6 BUS+ 19 SCI RX DATA
7 I/O 8 20 I/O 4
8 I/O 5 21 I/O 3
9 EMERGENCY 22 RSSI OUT
10 ANALOG GND 23 EXTERNAL MIC IN
11 FIL AUD OUT 24 AUX TX IN2
12 AUX RX IN2 25 UNIV IO OUT
13 MIC IN
The Ground Pin 4 is easy enough but I am not sure where to get PTT-In. I think I may have to program it as a I/O. I am assuming I can get voltage from the Bus+ pin 6 which should b easy enough to test with a multimeter. The Busy gate pin 5 seems clear enough. I think I should use Pin 11 Fil Aud Out to go to my Audio Input on the TAG. The rest seems fuzzy on what is most appropriate. Any assistance would be greatly appreciated.