XTL Radio

From W9CR
Revision as of 17:06, 3 March 2021 by Bryan (talk | contribs) (→‎Global Core Accessory Interface ("GCAI"))
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

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

XTL Accessory Jack Picture Radio Side, aka J2

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
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
Control Head (J1) TIB (J700)
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.

Pictures of Radios

Brick and TIB


Control Head Interface

XTL 2500 900 MHz Internal PCB

Control head interface

O series Transceiver Interface Board (TIB)

Mid Power Flex detail


XTL2500 Detailed Service Manual
XTL5000 Basic Service Manual