MAXTRAC programming

MAXTRAC: Try using the "Shift method" same as with the Radius and see if your version of RSS supports it. Otherwise, well, you will either need to do some Hex editing of your saved file or get a copy of the LAB RSS.
If you are going to use the Hex editing method, see the steps below.
In the MAXTRAC.MDF file make a Checksum-16 of the whole file (the F12 option in Hex Workshop), in our case we ended up with 0x4528 (RSS V 06.00), write this down, you might need it later.


Look starting at about offset 0x2BA, you should see something like:

The highlighted area contains all the bandsplits recognized by this particular RSS.

Maxtrac 50-54MHz (6 Meters) Amateur Radio Conversion

50-54MHz (6 Meters) Amateur Radio Conversion
You've got a Maxtrac/Radius that you want to tune up on 6m...


6m Maxtrac Modifications

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Ok, so you've managed to get some 6m frequencies programmed into your 60W 42-50 MHz Maxtrac/Radius, but you are having problems with the TX and RX locking up and working properly. Well, try the following fixes:

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Easy Fix
First, check the TX and RX VCO steering lines to make sure they swing between 2 and 8 VDC. If they don't, read on.
On the RF board under a cover are the VCOs for TX and RX. You should see a test point on the board marked SL. This is in the middle of a bunch of capacitors C109,C110,C111, C127.
This is the VCO steering line. While monitoring this point with a voltmeter, adjust L202 in the RX VCO section for around 7.8 VDC. Likewise, with the radio keyed, adjust L213 in the TX VCO section for 7.8 VDC (it helps to have a manual). The radio should work on six meters now although the sensitivity of the RX will be somewhat reduced because the front end of the radio falls off above 50 mHz.

Surplus Radio Guide Series, Programming Motorola Maxtrac & Radius models

Surplus Radio Guide Series, Programming Motorola Maxtrac & Radius models

Guide to surplus radio. Demonstrating the difficulty of supporting older commercial radio equipment. Introducing DOSBOX as a solution to programming and configuring older support programs. Long series in multiple parts starting with the Motorola family of commercial radios.

MAXTRAC | RADIUS

MAXTRAC/RADIUS

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In typical Motorola fashion, the Maxtrac and Radius line of mobiles are really the same radio! The only real difference is the actual firmware of the radio. All of the info provided here should work with varying degrees of success depending on the features of the original radio. The Service Manual is crammed full of stuff and would be well worth ordering if you plan to do any experimenting with the radio. The part number of the Service Manual is 6880102W84 for the Maxtrac and it contains info on all models of the radio (Low, VHF, UHF, and 800 MHz).
Do you need a pinout for the 16 pin accessory connector, the 5 pin accessory connector, or the mic connector, or how about the programming cable?
If you want to inject audio into your Maxtrac/Radius while tuning it up with the RSS, you will want to have a look at this schematic.
For a easy overview of all the programmable pin configurations on the accessory connector, check out this Excel Spreadsheet or this image.
If you want an easy way to connect to the Accessory Connector on these radios, you can order the HLN9242A or HLN9457A Accessory Connector kits. These include an accessory connector housing, some pins, and some wires with pins already attached. One thing to note, the HLN9242A kit also includes a pin extractor for removing previously installed pins.
If you would rather build your own accessory cables, the parts are available from DigiKey. You will want the following:

Information Common to Both Maxtrac and Radius

Information Common to Both Maxtrac and Radius
Since these radios are so much alike, lets start with some things you can do that apply to both series of radios.

Codeplug Checksum Location
If you happen to be messing around in the codeplug file, be aware that the first 0x2D bytes need to have the proper checksum (stored at offset 0x2E).
For example, if you wanted to calculate the checksum of the following header in a codeplug file:

You would select the bytes and do a 1's Complement Hex Checksum calculation.


The Checksum-8 value is the one you want to enter into offset 0x2E. In this case you can see that they already match.
We've been told that the same applies if you are changing the serial number of the radio using the EEPROM access feature of Lab RSS. The nice feature of using the Lab RSS is that it has the option to correct the checksum for you.

Maxtrac - Radius 900MHz Amateur Radio Conversion

900MHz Amateur Radio Conversion
The Maxtrac/Radius will work just fine in the Ham band. But, you will need to make some modifications to the RF section as well as some of the programming in order to get it to work properly.
Before you go any further, you must be trying to convert a 900MHz radio, these would be models that have model numbers starting with either D27 or D37. If you have a D35 or D45 radio, then you have an 800MHz radio, and you will not be able to convert these radios to the 900MHz band.
You can convert the trunking D27 "B2" radio, and make it into a 2 channel conventional radio.
If you want the straight forward instructions on converting the radio, then follow this link. The modifications presented there should provide sufficient results for most people.
If you are looking for an explanation on how the Pin Shift signal works and which VCO's do what, then you will want to look at the Pin Shift explained page.
If you are a die hard and want full coverage on transmit and receive, there are going to be some more modifications involved. You will want to investigate these modifications which came from Michael Roche, AA2LS.
You can also get a little help with some of the tune-up instructions if you check here.

Codeplug Hacking

Codeplug Hacking
Well, if you are brave enough to mess around in the codeplug using the EEPROM Access feature of the Maxtrac Lab RSS, there are some things you should know.
With version R07.02.00a Maxtrac RSS and newer, the codeplug errors you may get when reading the radio have been expanded from the usual Error #58 into a bunch of different codes. Depending on what the code is, determines the block of data in the codeplug which is corrupted. The blocks we have identified so far are as follows:

• Address 0x000 to 0x02D, checksum at 0x02E, Error #58
• Address 0x02F to 0x039, checksum at 0x03A, not checked
• Address 0x03B to 0x07E, checksum at 0x07F, Error #59
• Address 0x080 to 0x08B, checksum at 0x08C, Error #60
• Address 0x08D to 0x093, checksum at 0x094, not checked
• Address 0x095 to 0x09B, checksum at 0x09C, not checked

Making a Maxtrac do PAC-RT

Making a Maxtrac do PAC-RT
One similar way this can be economically achieved is by using a RICK unit, or building a repeater cable (see at the beginning of this page) yourself and plugging it into a second MaxTrac.
The second MaxTrac can be a simple 2-channel unit (or not) and will two-way repeat the first one and vice-versa. You can also construct this device to one-way repeat (just eliminating the second TX line) to construct a GMRS repeater out of two Maxtracs.
Otherwise, to actually use a PAC-RT with a Maxtrac you need the following cable:

MaxTrac     PAC-RT
Acc Conn. 
 3  -------------------- 6
 13 -------------------- 1
 11 -------------------- 21 (Shielded Cable)
 2  -------------------- 19 (Shielded Cable)
 7  -------------------- 8 
     ----- 2
     |
     ----- 16
     ----- 10
     |
     ----- 17

Cable shields are connected to PAC-RT Pin 18 (Ground) and not connected at radio. There are two jumpers inside the PAC-RT Connector, Pin 2 to 16 (B+) and 10 to 17 (PTT Ground).

For on-off control:
PAC-RT Pin 2 B+ to on/off switch  
 Pin 9 & 15 other side of on/off switch 
(Pin 9 = PAC on/off, Pin 15 = Portable in/out) 
Both must be connected to B+ for unit to turn on,
Pin 22 ground (not required, unless you want an indicator lamp, or something).

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Maxtrac Adding Type II/IIi Trunking

Adding Type II/IIi Trunking to a Type I Maxtrac
First off you must start with a B5 B6 or B7 model (has to be 16 pin ACC)
The second step is to obtain a type II firmware chip for a Smartnet Maxtrac, the part number is HLN9383.
Next, you need to blank the logic board using Lab RSS.
Re-program the logic board with your trunking RSS so that it is now a Smartnet radio (either a C3, C5, or C6).
Realign the unit and you now have a unit capable of type I,II, and IIi.

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Motorola MaxTrac Rear (jumpers)

Changing Band Limits in Maxtrac RSS Version 5.03

Changing Band Limits in Maxtrac RSS Version 5.03

Search for F6 46 FE 01 75 03 in file MOBILE5.OVL and change the 0xF6 to 0xC6.

Search for B8 00 00 76 01 and change the 0x76 to 0xEB.

You can now program any frequency in, it is a matter if the hardware will do it.

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Maxtrac Radius 9600 Baud Packet Conversion

9600 Baud Packet Conversion
The Maxtrac/Radius Series are 9600 baud packet capable. They do need a minor modification though. For RX, its no big deal, just take RX audio from PIN 11 of the Accessory Connector and swing JU551 to the (A) position (Flat RX Unmuted). For TX audio, you will have to run a jumper to the junction of R223, C228, R222 on the RF board to inject the data (if applicable you may need to set the deviation pot in the radio to maximum). You might want to put a pot on your TX line somewhat like the setup Motorola uses (voltage divider) to adjust the deviation. It would be wise to do some measurements to make sure you have the deviation correct. You might also want run the RX and TX pins to the unused pins on the front mic connector after the mods are done.