12V 60A car battery , maybe dead?

[Groundloop]

@UncleFester,

The BU208A is a excellent transistor for this charger. It can take the high voltage "spikes" without any harm to
the transistor. As I said in a earlier post, you can use a Ferrite rod (great source is in old defect PC power supplies)
as a core and then save a lot of magnet wire. With a Ferrite rod you can also use thinner wire. That said, the air core has proved itself as a simple and easy way to build this charger. The air core coil also has "better" properties when charging, than a Ferrite or Iron core. Please use the 18 gauge (1mm) for the main coil going to the transistor collector and use the 23 gauge (0,6mm) for the trigger coil. If you have enough 23 gauge then just use two in parallel for the output coil.
If you want to save money then you can omit the variable resistor and just use one fixed value (approx. 470 ohm 5W) resistor going from plus to the trigger coil. If you use a lab supply at the input then you can adjust the input voltage to suit your output needs.

I would also like to repeat some safety tips. Always connect the charge battery before switching on input power. Always switch off input power before disconnecting the charge battery. Always charge in a good ventilated area. Never charge a battery without supervision. Never overcharge a battery. Always check that the battery has the correct water level. Refill with distilled water if low water level. If the battery is defect (short circuit) and all you get is a warm battery with no voltage climb then stop the charger and recycle the battery to the nearest recycle station. This charger can not repair a shorted battery cell.

Groundloop.

[UncleFester]

@Groundloop

Thanks for the input. Last question:

Can I use a normal wire spool of 30mm Inside diameter or is this too small? (I guess it's similar to the Bedini coil forms)

Thanks,

Tad

[Groundloop]

@UncleFester,

No.

You will need a spol with approx. 100 mm diameter.

Groundloop.

[Groundloop]

@UncleFester,

So, did you get it to work? Is the circuit restoring old batteries?

Regards,
Groundloop.

[UncleFester]

I have more wire coming this next week and the circuit portion is already soldered onto a circuit board. So almost done = )

Thanks,

Tad