Bedini Fan charger, Need Help please...

[muddasar48]

PLEASE help me...!
I recently build my bedini fan charger, it runs smoothly but i am not getting
spikes or high voltage. i checked the voltage at collector approx. 5v-6v.

Source Battery:12v
charging battery:9v
Transistor: Tip31c (high power BJT)
Diodes: 1n4001,1n4007
using 12v PC fan (Coil Resistance 37ohm both for trigger and drive coil)
5K pot.

Also it is not self running, source voltage drops continuously.Although the charging battery shows an increase in voltage but as i disconnect it from the cct the voltage continuously drops to original value !!!???

Any Suggestion...
Thanks

[John_K]

It's not a self-runner

PLEASE help me...!
I recently build my bedini fan charger, it runs smoothly but i am not getting
spikes or high voltage. i checked the voltage at collector approx. 5v-6v.

Source Battery:12v
charging battery:9v
Transistor: Tip31c (high power BJT)
Diodes: 1n4001,1n4007
using 12v PC fan (Coil Resistance 37ohm both for trigger and drive coil)
5K pot.

Also it is not self running, source voltage drops continuously.Although the charging battery shows an increase in voltage but as i disconnect it from the cct the voltage continuously drops to original value !!!???

Any Suggestion...
Thanks

What you have posted sounds perfectly normal. This is not a self runner, the primary will run down and the secondary will charge up. If you have it tuned correctly, you can get almost 1:1 charging, plus all of the air the fan is moving (work).
When the primary has run down, you just swap the batteries around.

You should also do some research on how batteries react when being charged and discharged.


John K.