Motorola Maxtrac Question

[yardbirdjr]

Hello All!

I have a nice Maxtrac Low Band that is on the 42-50 Mhz split. It is 6 Channels

I was just wanting to see if it is possible and worth the time and money to convert it to either 16 or 32 channels and scan.

Please advise

Thanks

David

[PETNRDX]

If it has a 5 pin logic board, it might only be able to go to 16 ch.
But, if it has a 16 pin logic board, then it can be blanked and reinitialized as a 32 channel "High Signaling" model with scan, channel number "alias" etc.
It is pretty common to do that.
There is a thread further down discussing how to do it.
(The other fellow is doing a 29 mhz one, but its the same process)
Definitely worth doing.

[kf4sqb]

While you can add more channels, you can't get it to scan more than 16 of them at the time.

[kc7gr]

I've done several of the low-band Maxtrac conversions. Yes, it's possible, but doing it right will require a service monitor. This is mainly because you need to do some tweaks to the receiver's front end, in the form of putting stainless-steel or brass set-screws into some of the coil forms. The fact that the screws are non-ferrous creates an anti-magnetic effect which actually lowers the inductance of said coils, thus allowing the front end to push up above 50MHz.

I've also found, in most cases, you need to modify the PA power control circuit to allow for manual setting with a trimpot. This is because the firmware doesn't deal well with frequencies above 50MHz where power output is concerned.

There are good instructions on both the regular Batlabs site and on repeater-builder.com. If, after examining this material, you decide it's too overwhelming or you don't have the test gear or skill needed, I can do the conversion for you at my normal rates.

Happy tweaking.