Batboard

Does this make sense to anyone else?

If the plug is oriented "TAB ON TOP" then the RJ45 pin 1 and 8 would be opposite from what this shows.

Is ground pin 4 and bus+ pin 7?

YOU ARE EXACTLY RIGHT, it is numbered backwards. it should use the solid orange and blue stripe wire if i'm not mistaken.

The key to remember, on the Maxtrac, Radius, GM300, etc.. Pin 1 of the mic connector is the top of the jack towards the volume control.

So the way that picture is oriented is correct, however they really need to put a note on there with an arrow saying something like pin 1 UP, etc.

kb0nly wrote:The key to remember, on the Maxtrac, Radius, GM300, etc.. Pin 1 of the mic connector is the top of the jack towards the volume control.

I'm not sure how to interpret that looking at the M1225 sitting here in front of me. The mic jack is directly underneath the volume control, oriented horizontally. There is no single pin "towards" the volume control.

The M1225 cable pinout on batlabs is incorrect (and doesn't work). I reverse engineered a Motorola programming cable today and found this to be the correct pinout (and it works):

(DB25 pin to RJ45 pin)

24 to 2
16 to 3
1 to 5

Pins 11 and 4 on the DB25 are jumpered together.

That makes TWO batlabs cable pinouts incorrect in a row. The first I tried was the incomplete HLN9742 flash cable pinout.

Yes, the connector is horizontal on the M1225, but we were talking about the Maxtrac/Radius mobiles on which the mic jack is vertical.

As for the programming cable, i don't know what to tell you there, i have programmed a many M1225's with my Maxtrac cable, i have programmed nearly a hundred Maxtrac/Radius mobiles now using a cable i made from the pinout on the batlabs site.

So i don't how to explain your problems with it. But the diagram in the first post IS CORRECT, always has been.

Earlier, you determined the wiring on your M1225 programming cable:

(DB25 pin to RJ45 pin)

24 to 2
16 to 3
01 to 5

I suggest that you've got the pins mis-numbered on the RJ45 end. If you were counting from the wrong end, these would correspond to:

(DB25 pin to RJ45 pin)

24 to 7
16 to 6
01 to 4

RJ45 pin 7 is the programming pin. RJ45 pin 4 is ground. RJ45 pin 6 is the PTT line. I've heard that some interface cables will have PTT wired up for testing, but it is not necessary for programming. All you need is pins 4 & 7.

I know that the standard MaxTrac cable, as wired according to the info on BatLabs, works with MaxTracs, Radiuses, SM50s, GM300s, and probably a few others. There is certainly some stuff that's out-of-date, misleading, or incorrect on BatLabs, but not this.

Bob M.

I'm reading the RJ45 pins from the cable end of the connector, with the tab facing down, starting from 1 on the left to pin 8 on the right.
Is this not how the RJ45 pinout works?





Even if I did have it backwards, the only valid connection (according to the diagram here on batlabs) would be DB25 pin 1 to RJ45 pin 4.

I just checked my service manual to find the mic connector on the radio is BACKWARDS from the RJ45 wiring standards above.

Here is the pinout I determined yesterday from the Motorola cable, now with pin descriptions and Motorola's numbering scheme:

rib DB25 pin 24 (BUS+) to mic pin 7 (SCI)
rib DB25 pin 16 (NC) to mic pin 6 (MIC PTT)
rib DB25 pin 1 (GND) to mic pin 4 (GND)

Part of the problem here is that I was talking "RJ45" wiring while Motorola makes up their own backwards thing.

Check out the RLN4008B diagram:



Pin 15 and 24 are the same. This is why the pinout on batlabs works, but it's still not the way the actual Motorola Radius programming cable I disassembled the other day was wired.

You are correct if you're talking about a standard wired NETWORK connection, or Bell Laboratories' intended use of these connectors.

Motorola's usage of the RJ45 connector does not, nor does it have to, resemble anything else you may find on the internet or in other books, real or imaginary. Pin 1 on a MaxTrac is the upper-most pin when looking into the microphone jack on the front of the radio.

Their pin numbering was done to suit themselves. You have no choice but to submit to their convention, as odd or incorrect as it may seem.

Those of us who have made or use programming cables on MaxTracs have referred to the official Motorola Service and Programming Manuals and are giving you the information that works for these radios.

Bob M.