Hobbyking 20A UBEC
1st pic front view of esc
2nd pic backside view
3rd pic frontside view
4th pic front view
* Esc has 25V 470uF capacitor
* On backside esc has 1 microcontroller I.C. and 2 transisters and resisters,diodes
* on frontside esc has light weight metal piece to absorb heat(i believe)
* below metal piece there 6 transisters.
NOTE:
- i can not see any component(buzzer or speaker) that can produce voice!!!!
- One more thing is you can repair your esc by replacing capacitor but i haven't tried it and i am not sure whether it works or not.