Interface URI to Motorola

For all of these configurations, if you wish to connect an EEProm to save parameters, please see https://wiki.allstarlink.org/wiki/Interface_EPROM_to_URI

Motorola Desktrac Repeater - Flat audio

Tie Desktrac 20 and 21 to Desktrac 8 Tie URI 22 to URI 24 URI 1 - Desktrac 13 URI 12 - Desktrac 22 URI 20 - Desktrac 6 (Gnd, Shield) URI 21 - Desktrac 23 URI 25 - Desktrac 3

Motorola Desktrac Repeater - Processed audio

Tie Desktrac 20 to Desktrac 8 URI 20 - Desktrac 6 (Gnd, Shield) URI 21 - Desktrac 15 URI 22 - Desktrac 16 URI 1 - Desktrac 19 URI 8 - Desktrac 9 (COR Det.) URI 7 - Desktrac 12 (CTCSS Det.)

Radius/Maxtrac series with 16 pin accessory connector - Simplex - Flat audio

URI 20 - Radius 7 URI 21 - Radius 11 URI 22 - Radius 5 URI 1 - Radius 3

Radius must have JU551 in position 'A' (flat audio out).

Radius/Maxtrac series with 16 pin accessory connector - Simplex - Processed audio

URI 20 - Radius 7 URI 21 - Radius 11 URI 22 - Radius 2 URI 1 - Radius 3 URI 8 - Radius 8 (COR/CTCSS Det.)

Radius Must be programmed to output COR/CTCSS det. on pin 8 of accessory connector, and JU551 in position 'B' (de-emphasized audio out).

Pair of Radius/Maxtrac series with 16 pin accessory connectors - Duplex (Repeater) - Flat audio

Receive Radio URI 20 - Radius 7 URI 21 - Radius 11

Transmit Radio URI 20 - Radius 7 URI 22 - Radius 5 URI 1 - Radius 3

Radius receive radio must have JU551 in position 'A' (flat audio out).

Pair of Radius/Maxtrac series with 16 pin accessory connectors - Duplex (Repeater) - Processed audio

Receive Radio URI 20 - Radius 7 URI 21 - Radius 11 URI 8 - Radius 8 (COR/CTCSS Det.)

Transmit Radio URI 20 - Radius 7 URI 22 - Radius 2 URI 1 - Radius 3

Radius receive radio Must be programmed to output COR/CTCSS det. on pin 8 of accessory connector, and JU551 in position 'B' (de-emphasized audio out).

Getting twice as much level from the URI

If your radio requires more then the output at pin 22 is capable of delivering, you can take the wire that was going to pin 22, and move it to pin 12, jumper between pins 22 and 24, and apply +12 Volts to pin 25. This will pipe the output of the URI through the built-in 6db gain amplifier and give you enough output level for your radio.