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

Panel Numbers for Lab RSS

Panel Numbers for Lab RSS
OK, so you're hacking your poor Maxtrac with Lab RSS and have blanked the board. You are in the process of re-initializing the logic board using the Replace Logic Board options in the Service Menu. BUT, you've hit a snag... the RSS is asking you for something called a "Panel Number". What the heck is that?! Well, look no further. If you had been wise and used the built-in help (F1) when you got to this point, you would probably have found the following list, but you didn't, and now you are here.

Here are the panel numbers used when re-initializing various flavors of Maxtrac:

Panel Number	Description
0	All 2 frequency models: Radius M100, Maxtrac50, Maxtrac100; Voice Reporter Models: H1135_, H1136_, H1138_, H1139_, H1134_
1	All 6, 16 and 32 Frequency Models: Maxtrac 300
2	All 6 Frequency Models with Signalling or Accessory Connector Option: Maxtrac 300
50	Maxtrac 820 Trunked: D__MQA5GB5_K, D__MQA5GB1_K; Privacy Plus 250/750: T_5CPA5___H
51	Maxtrac 820 Trunked: D__MQA5GB3_K
52	Maxtrac 840 Trunked: D__MWA5GB5_K, D__MWA5GB6_K
53	Maxtrac 840 Trunked: D__MWA5GB7_K
54	Maxtrac 840 Trunked: D__MWA5GC0_K
55	Trunked Voice Reporter: H5011_
56	Maxtrac 820 Trunked: D__MQA5GB4_K

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RADIUS programming

RADIUS:
Life can be a lot easier for Radius owners. All you have to do is load your file into RSS, go the channel you want to program, when you are in the field you want to change, use the shift key and the numbers across the top of the keyboard to enter the frequency. Fill the entire field and make sure you release the shift key when you enter the decimal point. ie. 139.5500 would be !#(.%%)) Its as simple as that.

If the above method doesn't work, then you'll have to do some hex editing.
In the RADMBL.MDF file make a Checksum-16 of the whole file (the F12 option in Hex Workshop), in our case we ended up with 0xA402 (RSS V 08.00), write this down, you might need it later.


Look starting at about offset 0x29E, you should see something like:

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

A single bandplit entry in the table looks like:

If you look carefully at the highlighted portion, you should notice the following items>
02 00 = Bandsplit identifier (Note: it is at the end of the frequency assignments)
E4 05 = 1508 in decimal, ie 150.8000 MHz
54 06 = 1620 in decimal, ie 162.0000 MHz
Note there are 3 occurances of the strings E4 05 and 54 06. The first set is the limits displayed in the Radio Wide menu (F4-F2). The second set are the TX limits for the radio. The third set are the RX limits for the radio (note that if the TX and RX limits are not set the same the RX limits are screwed up).
To figure out what hex to enter for your bandsplits you can either use the Base Converter (in Hex Workshop), or use a calculator with a HEX --> DECIMAL conversion function.

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

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.

Pictures