Batboard

Hello everyone,

I am looking at picking up a Maxtrac Low Band VHF Model D51MJA93A5AK, and was wondering if it is possible to modify the code plug to give you more then 2 channels on this model? If so how do you keep track of what channel you are on without a display?

Thanks, Chris

If the model number specifies 2 channels, that's all you can get. The two-channel control head will only toggle between the two channels that the codeplug can store.

To get more channels you need to replace the front panel and maybe the firmware. After that you'd need to blank and initialize the radio, and the model number would change to reflect the greater channel capacity.

However, with some radios, the logic board won't allow you to do that. Not impossible, but by the time you get done with the conversion, you might be better off buying a radio that can already do more than 2 channels. The key is in the model number: the 8th character "3" corresponds to 2 channels. Values of 7, D, J, or P mean 6, 8, 16, or 32 channels, respectively, for most conventional MaxTracs.

Bob M.

Just to add to what Bob already posted.

Is the radio a 16 or 5 pin accessory connector on the back? If it's a five pin then chances are you can forget about it, there are exceptions to that rule but that requires opening it up and seeing what number the logic board is.

If it's a 16 pin radio then there is a distinct possibility that with a new front panel and a firmware upgrade it could be made into a 16/32ch radio.

Also, some 16-pin logic boards already have firmware that will do 2, 6, 8, 16, or 32 channels. Blank it, initialize it, and try it. If it won't do more than 2 channels, you can always blank it and reinitialize it to a 2ch radio and you're no worse off than when you started.

Bob M.

I have found both a 6 and 8 channel radios both of whom have 16 pin accessory connectors. Can I just modify the code plug in these or do I have to load new firmware? If new firmware, where can I get it/

Thanks, Chris

You'd have to blank the board with LAB software, then initialize it with regular software, choosing the options you want (channels, signaling, power, scanning, etc.). This process also requires you to open the radio as you'll need to enter some numbers on stickers as well as the 9.6V supply voltage. If you don't have all the required equipment and program to do this, there are plenty of people on the BBS who do, and it's really an easy procedure (once you've done it a dozen times).

Bob M.