GP300 post and pre 1994 differences

[Josh]

I hate to talk about older radios because most of the time people aren't trying to get more features out of them and have moved on.

I know that older 2 channel GP300 radios that exhibit the "12222222" on the channel selector can have channels added, but those that go "121212121212" cannot. My question is simply whether it's the binary channel selector that is different, thus preventing the additional channels from being accessed, or is it something else?

Has anyone upgraded a 1994+ GP300 2 channel radio for more channels? I'm curious as 2 channels and no signaling isn't enough, not to say that I'm too poor to buy another GP300 with 8 or more channels.

-Josh

[Will]

The channel selector switch IS the same. The microprocessor is different in the later radios.

[Satelite]

Hello:
As Will already stated the microprocessor was changed by motorola in mid 1994 to stop the GP300 radios from being upgraded. ( So i have been told anyway )
I tried to gain the DTMF phone capability and didnt care if it was only a two ch model = On a newer 1994 radio.
But that feature was not availble per the newer changed microprosser .
It was my understanding that motorola removed the address lines in the microprosser needed for the other features not intended for the 2ch GP300.
So unless your willing to change out the microprosser your pretty much stuck with a basic 2ch GP300.
Satelite

[Josh]

fine business, thanks