rcb6i radio giving only a range of 15 meters from the receiver.. is there any way to troubleshoot it by ourselves? I did open the tx and there seems to be nothing wrong with it (as far as I know). could somebody help?

@manu,
Check if the solder joint of the antenna is broken (both Tx and Rx)
Regards

the solder joint of rx was broken, i soldered it back but the problem is still persisting sir.

Try with another Rx (borrowed)
If you are in Indore, there are 2-3 guys with the same RC...
Chances are Rx antenna not connected properly