Joule Thief

MrMag · January 13, 2011, 04:39:09 PM

Quote from: dasimpson on January 13, 2011, 03:49:19 PM
because diodes have a forwed voltage drop

Maybe, but aren't you charging the cap with the spikes. I don't think it would bother it. I've never worried about the forward voltage drop. If you think about it, every device and even wire itself does have some resistance that would cause a voltage drop. So, if you want to get the most out of your EB, you would also want to make sure that all your connections are as short as possible and soldered. You probably loose more voltage on the wire from your EB and the connections then you do with the diode. I think the advantages overcome the minimal voltage loss. However, I've never tried it myself, so I could be wrong.

dasimpson · January 13, 2011, 04:42:20 PM

Quote from: MrMag on January 13, 2011, 04:39:09 PM
Maybe, but aren't you charging the cap with the spikes. I don't think it would bother it. I've never worried about the forward voltage drop. If you think about it, every device and even wire itself does have some resistance that would cause a voltage drop. So, if you want to get the most out of your EB, you would also want to make sure that all your connections are as short as possible and soldered. You probably loose more voltage on the wire from your EB and the connections then you do with the diode. I think the advantages overcome the minimal voltage loss. However, I've never tried it myself, so I could be wrong.

yes but when your only getting .80 volts and voltage drop can be 0.7 it soon makes a difference plus the fast of current drop on a diode also i guess if you used 1n914 diodes you wold be better off but yeah i do agree a diode is needed just a matter of finding the lowest voltage drop diode you can get

Pirate88179 · January 13, 2011, 05:13:12 PM

Hey, what about using an LED? What is the voltage drop on that? Even if it does not light up...who cares? It is still a diode after all right? Just a thought, I have not tried this and have no idea if it is useful or not.

Bill

dasimpson · January 13, 2011, 05:14:33 PM

Quote from: Pirate88179 on January 13, 2011, 05:13:12 PM
Hey, what about using an LED? What is the voltage drop on that? Even if it does not light up...who cares? It is still a diode after all right? Just a thought, I have not tried this and have no idea if it is useful or not.

Bill

i think the ability of reverse voltage and current comes into play

dasimpson · January 13, 2011, 05:16:07 PM

just look up on specs for forwed voltage drop what the reverse current is that can be handled i thin the 1n914 should do the job well if i remeber right they have a very low voltage drop
but if how you do it now works for you why change it