I think i know the answer but i just wanted confirmation. is there a way to expand the frequency range on a motorola HT1250 LS+? for example the one i have is for 420-470 but i would like to be able to use it through 512. i know with some of the chinese model radios such as the wouxun kg-uv2d it is just a software change and was hoping the same was true for the ht1250
As you will find with the older radios, you probably can hack the software and get the radio to go outside the normal range. However, in this case, you are probably going to be looking at some major issues. The first one is the VCO (voltage controlled oscillator) that controls the frequency generation in the radio. It will not spread that far.
Then you have the issue of the tuned RF circuits. Again they can only stretch just so far. Once you get outside that range, the results are no transmitter power and very poor receiver reception.
The radio is made in different frequency segments so that the electronic circuits can be made to function over those segments. to ask the radio to go way outside of those segments is like asking your car to go further than the fuel supply will allow. Something has to give. Your car will run out of gas. The radio will run out of the VCO lock range it was made to function in.
The simple answer is it won't do it.