Hi! all
I have bought a Honda trail 70 that have no lights (All burned) so I would like to add LED on 12Vdc.
The thing is , the AC from the generator is 9 to 34VAC on one side and 11 to 42Vac on the other.
9Vac is idle and 34Vac is almost high RPM. I tried LM7812 that work quit good (Very hot on heat-sink)
for lower then .400A but I can't go higher than 30, the IC cut to protect himself. I tried a Buck converter
LM2596 but became very hot without being able to put some Heat-sink on it. I put a diode to cut in half
the pulse from AC, plus a 1000uf for filtering. I try some resistor (2-4-6 ohm) between the AC and the
diode but I loose the lower volt, so the head light doesn't work properly.
My question is: What can I build to have a regulator that can accept the 9 to 34Vac and keep the
12Vdc as output at 2A for the headlight , or if possible 3A (to include the brake and park lights)
(I know that at low input volt, the output will be lower than 12) but at least there will be some.
And I like too, to be able to build another one that can go down to 6Vdc cause the lights inside
the speed-o-meter are still 6v. No LED as small enough (For now) to fit inside. No more battery
inside the bike (No use anyway).
Many thanks to anyone that can help. I'd like to build it and learn by the same time.