Page covering the XTL 1500/2500/5000 Radios

These are P25 trunking radios which are mono-band.

Accessory Connector

J2 is the accessory connector

Here's a picture of it from the radio side

Table of Pins

Rear Accessory Jack Pin Functions
Pin	Name	Function
1	GRND	Ground
2	BUS+	SB9600 BUS+ Data
3	BUS1	SB9600 BUS- Data
4	TXD	RS232 Transmit Data
5	RXD	RS232 Recieve Data
6	USB-	USB - (White)
7	USB+	USB + (Green)
8	RESET	SB9600 Reset
9	BUSY	SB9600 BUSY
10	CTS	RS232 Clear to Send
11	RTS	RS232 Request to Send
12	USB PWR	USB Power +5v
13	CHAN ACT	Chanel Activity (COR+PL
14	GRND	Ground
15	EMERGENCY	Emergency
16	PTT	Push to Talk
17	ONE WIRE	One-Wire Data
18	VIP OUT 1	Vehicular Interface Output 1
19	VIP OUT 2	Vehicular Interface Output 2
20	SPKR+	Speaker+
21	RX FILT AUDIO	Receive Filtered Audio Out
22	Monitor	Monitor Overrides PL
23	AUX MIC	Rear Mic Input
24	SW B+	Switched Battery Voltage
25	IGN	Ignition Sense
26	SPKR	Speaker -

My connections

The below is how the XTL's installed in my vehicle are connected:

26,20 - speaker
14-15 - Jumper for Emergency
    7 - USB + (Green)
    6 - USB - (White)
    1 - USB Ground (Black)
   12 - USB 5V (Red)
   25 - Ignition Sense

Control Head:
Red - Constant 12v
Yellow - Ignition 12v
Black - Ground

Sourcing of connector

As of now, there is no other source for the connector than Motorola. The rumor mill puts money on ITT Canon being the manufacturer.

The pins come in a 25 pin strip Motorola Part Number: 3980034F05

The housings are HLN6961

The body looks like 2 D-Sub connectors stacked with standard pitch spacing on the pins.

Aftermarket Pins will not work due to the low profile retaining ring. This thread on the Batlabs Batboard has some more info and this picture showing the differences below:

XTS accessory Pin detail vs. normal pins

Notes on assembly

The TE 91285-1 Pin extraction tool is highly recommended. DigiKey Link

The Engineer PA-09 is recommenced as a crimper.

Photos of connector

I disassembled and took some close up pictures with my scope. The connector looks a bit similar to most D-SUB connectors.

Global Core Accessory Interface ("GCAI")

This is the connector used for mic jacks and such. It's also used to keyload on the brick (remote mount) or via the control head (dash mount).

GCAI Connector both

GCAI Pinout

CGAI Pin Functions
Pin	Signal Name		Description	RJ-45 Pin	Color
Pin	Control Head (J1)	TIB (J700)	Description	RJ-45 Pin	Color
1	One-wire	One-wire	Signal used to identify accessory.	3	Orange
2	PTT	AUX-PTT	Active low Push-to-talk input. Asserting this input on the TIB results in auxiliary microphone input use (GCAI pin 7).	5	Brown
3	SPK	NC	Receive audio out designed to drive a 150Ω load.	NC	NC
4	USB_D-/RS232_RX	Mid-power: RS232_RX only High-power: USB- / RS232_RX	Multiplexed USB D- and RS232 receive signal. Mid-power transceivers do not support USB at the TIB GCAI connector. The RS232 signals are CMOS levels, 0-5 volts.	8	White
5	Ground	Ground	Ground	2	Black
6	VBUS / OPT_5V	VBUS / OPT_5V	On the control head, when the GCAI port is configured as a device, this is the VBUS input used for enumeration. When the GCAI port is configured as a host, this is the VBUS output, capable of sourcing 500mA. The TIB GCAI port can not be configured as a USB host.	1	Red
7	MIC_HI	AUX_MIC	Microphone input.	4	Blue
8	USB_D+/RS232_TX	Mid-power: RS232_TX only High-power: USB+ / RS232_TX	Multiplexed USB D+ and RS232 transmit signal. The interface used is based on a one-wire read of the connected accessory. Mid-power transceivers do not support USB at the TIB GCAI connector. The RS232 signals are CMOS levels, 0-5 volts	7	Green
9	HUB / KEYFAIL	KEYFAIL	Multiplexed HUB and KEYFAIL lines on the control head. The TIB only has KEYFAIL.	6	Yellow
10	GPIO_0 / PWR_ON	GPIO_0	On the control head, this pin can be used by an accessory to turn the system on.	2	Black

Thoughts, it's likely that you can use the mic cable as a keyload cable. Looks like you'd need a RJ-45 jack and to plug into the TIB directly with it. Since it's multiplexed on the control head, it likely needs something to bring that to the right state.

Operational notes

The 900 MHz radio has an option for the pre-amp, you want this enabled.

The other concern for 900 MHz was the preselector B7250, and it's the same device from the MCS2000. Motorola describes it as a 6 MHz wide unit centered on 938 MHz, and then another follow the pre-amp for an image filter. In testing with a tracking generator it was found roll-off didn't happen until about 915 MHz and 960 MHz. This should be (and is) a fine ham band receiver.

The programing info for modifying CPS to program the hamband is on the XTS 2500 page.