View Single Post
  #20 (permalink)  
Old 11-08-2007, 12:19 PM
Mario's Avatar
Mario Mario is offline
Member
 
Join Date: Apr 2007
Posts: 34
Quote:
Originally Posted by Ewhaz View Post
Well, I have the right transistor thankfully, but I did notice the difference after you pointed it out. Maybe this was enough distortion so that the powers that be would leave it alone, who knows?

But yes, changing the duty cycle on a 555 would be a real pain. I'm assuming that the higher the frequency the longer the on cycle would have to be in order to allow it to reach saturation before the field could be allowed to collapse. Most likely this would require a lot of tuning. Still, at least its an option to explore later on circuits with different applications.

Still, what about the capacitor? The voltage on it is not listed for the charging side capacitor (not the timing). From what I've read, you have to be careful not to 'hit' the battery too hard, or it will cause a cascade effect that will cause the battery to explode, or at the very least be damaged. Is there a correlation between the type of battery to be charged and the maximum voltage that the capacitor can deliver safely?
Hi Ewhaz,

I'd take a cap rated in the 400-600V range from about 3 to 10uF. The voltage to the battery depends on the dump speed meaning the time you let the cap get its charge from the coil. I've noticed that the faster you dump the quicker the charge rate of the battery, even if the voltage is only about 30-40V. But I've also dumped at over 100v to the batt... I don't know what the max safe voltage is for a given battery, sorry.

regards,
Mario
Reply With Quote