Problem with range of a remote control alarm for a car

i buy a remote control /alarm/ for my car it has a RF modul decoder MCU and relays, but the range is too short i don't know why. It nas a antena/wire/ around 20-30 sm/7.9 inch/ i change the battery - no efect. The distance of work is arount 1-2 inch :(((((( I planning to change the MCU with ATMEL MCU and rewrite the firmware :)

Thanks

Hi,

There can be 3 reasons for the very short range.

1) Receiver's sensitivity become very low
2) Transmitter in the remote modul has lower output power than it should have
3) Transmitter and receiver are at off frequency (they do not work on the same RF frequency, they got detuned with respect to each other)

Maybe the best cure is to return the whole unit to the dealer and change it for a good unit unless you have the proper skills and instruments to focus on the fault.
Do not make any changes on the MCU or rewrite till the unit does not operate for the correct range / distance it was designed.

rgds
unkarc

i've done

just opening the remote and tune the trimer :)))) it's word now about 6-7m
/~2800inch/

i just test it on that distance becouse on long distance i can't heart the relay :)))))