Batboard

Hello everyone.As a firefighter,My hobby is collecting dispatch consoles.I am setting up a Motorola Command Plus console with a CPI MR202 tone panel to run a Maxtrac 300,6 channel,30-50 watt.136-174 mhz radio.I know this radio is not narrowband compliant but I have heard that there are components in the radio that can be replaced that will make it narrowband compliant.Is anyone familiar with this?

Hello:
Yes the Maxtrac if it has the 16 pin logic bd HLN9313 can be narrowed banded and Motorola did at one time supply the conversion kit.
Id have to look at the kits info again but think it could convert a 5 pin bd too but don't recall which bd off the top of my head now.
But the fcc does not recognize a converted maxtrac to narrow band as a compliant legal radio.
Yes it does tx and rx as a narrow band per specs but again just not type accepted even if modded.
I still have the kits to mod the maxtrac in my inventory for doing the nb mod but later found out its not accepted per fcc rulings as legal.
Just the way the ball rolled for me when I years back grabbed kits to stay legal with the maxtrac but nope didn't work out in the end as a fcc accepted mod.
Satelite

To expand on what Satelite said, converting an older radio to narrowband generally involves changing the receive IF filters to narrow versions, and changing a few resistor values to lower the transmit deviation and increase the receive audio level.

The main reason the radio will NOT be narrowband compliant is because the reference oscillators in the older radios had 5 part per million frequency stability, while the FCC requires narrowband radios to have at least 2.5 ppm stability (twice as stable).

The other problem is that the radios may not be programmable for all of the 12.5KHz channels.

there plenty of Narrow band stuff thats out and cheap

Thanks for all the info.The main reason I'm using a Maxtrac is that the used tone panel I bought is for the Radius and Maxtrac line of radios. This console setup is mainly for display but everything works like it should.I am a firefighter/EMT and I have newer narrowband radios for that use but I thought if the MaxTrac could be updated I could use it if I had to.

Hello:
If the console is also able to use the Radius line as you say then :
You could take a GM300 which was also made from the Motorola factory as a 12.5 narrow band fcc compliant radio.
I have some in inventory yet.
Still have customers using the GM300 factory narrow band radios.
That way if you do decide to use the console the gm300 narrow band mobile would keep you narrow band compliant since its fcc type accepted per narrow band specs.
PS the GM300 does all the normal freqs but wont do the new splinter freqs unless you shift key program and retune.
Satelite

Your other option is to start using Radius M1225 radios. The M1225 should work fine with your MaxTrac/GM300-configured tone remote interface, and it supports wide and narrow band. They are pretty cheap.

Your other option would be the CDM series radios. Again, same plug as a MaxTrac/GM300, same pin configuration (for the most part), and wide/narrow selectable.