DiY for circuit repair

Thread Starter


Joined Apr 3, 2021
i am having a problem with my Valkano Bluetooth speaker. The charging port broke so i tried bypassing through by feeding the battery. Still it was just going on than off. So investigated the circuit board and find that @ C1 and R3 some damage happened now fixing it is what i dont know.. Help please!

Is there a way to bypass that? Any hack to give it power.


Joined Jan 8, 2017
You have not given enough information. Looking online there seems to be a number of different models Valkano Bluetooth speakers and I can't find a schematic for any of them. Looking at your picture there is a large inductor which I would guess is part of a switch mode battery charging circuit. I think it is probable that the external power supply is a higher voltage than the battery voltage so connecting it directly to the battery connections will probably have done some damage to semiconductor components. You would need to trace out the schematic of the parts between the external power input an the battery connections as a start to understand what components are likely to be damaged or destroyed.



Joined Sep 9, 2010
Looks like C1 is gone. You could try adding in a capacitor but I have no idea what value. Probably rated to at least the supply voltage, maybe twice that. Total guess but you could try 0.1uF

Finding another one to use as a guide is sometimes helpful. It allows for probing voltages and that can help diagnose the problem.