Btw does your PPM pulsewidth move when you press in the trigger on the controller?
yes, it moves.
but you have no pictures of the motor configuration in the vesc settings that I asked for.
I am just guessing here. If you have Motor Max and Batt max at same value it will create an issue? Try to make motor max higher then batt max
how do you think, is this one is good? http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=221101999&uq=636244555750998515
The DRV might not be the issue here… look more like a bad ground connection, since the voltage reading is directly on the mcu…
well sounds complicated/ i didnt quite understood everything you told, but ill try to figure it out
The reading for the voltage in the bldc tool are not made by the drv, but directly by the mcu. So, if you get a fluctuation on the voltage reading, it is most likely to be a ground problem (bad connection), battery problem or mcu problem (or R4, R3 are not the right value)
fluctuation on the voltage reading are only when receiver connected.without receiver there are no fluctuations
Are you able to run a motor detection, and run the motor in the bldc tool without the receiver plug, if so… you probably have a problem with your receiver. You might want to try another one before changing the drv 
If you can’t run a motor detection, it’s moat likely to be a bad ground connection somewhere over the VESC
no, motor detection is not working, in bldc tool i cant run it with arrows.
i figured out that burned DRV8302. it is seriously damaged. but how did i damaged it? by plugging vesc wire and external ubec wire into reciever in the same time?
Oh this is these vesc… If I can suggest you something, Is to buy legitimate VESC. Because routing a vesc is a art and these look badly made.
Probably a bad connection somewhere, if you had problem before connecting the ubec