Can anyone explain this? (electronics question)
Posted: Tue Jun 08, 2010 5:29 am
I was messing around with the basic joule thief circuit (the bog standard version, not one of the improved ones) the other day and noticed somthing odd which I can't figure out.
Basically, if I disconnect the negative leg of the LED, and touch it (while not touching any other part of the circuit), the LED dimly lights. If I hold my hand near the toroid while doing this, it gets slightly brighter. It also becomes much brighter if I touch the positive end of the battery with my other hand.
Lastly, if hold the LED in such a way so that both legs are being equally gripped, it still lights.
I'm at a loss as to why this happens... my first thoughts were either some kind of induction or capaciatence causing it, but my electronics knowledge is rudimentry at best so I'm really just blindly guessing. Anyone have any idea what's going on here?
Here's a few pics to illustrate it:
First up, here it is running normally:
Now it's got the negative leg disconnected:
This is what happens when I touch just the negative leg:
And if I touch the positive end of the 1.5V AA with my other hand at the same time:
Lastly, here I'm touching both legs of the LED but nothing else:
EDIT: 1000th post!
Basically, if I disconnect the negative leg of the LED, and touch it (while not touching any other part of the circuit), the LED dimly lights. If I hold my hand near the toroid while doing this, it gets slightly brighter. It also becomes much brighter if I touch the positive end of the battery with my other hand.
Lastly, if hold the LED in such a way so that both legs are being equally gripped, it still lights.
I'm at a loss as to why this happens... my first thoughts were either some kind of induction or capaciatence causing it, but my electronics knowledge is rudimentry at best so I'm really just blindly guessing. Anyone have any idea what's going on here?
Here's a few pics to illustrate it:
First up, here it is running normally:
Now it's got the negative leg disconnected:
This is what happens when I touch just the negative leg:
And if I touch the positive end of the 1.5V AA with my other hand at the same time:
Lastly, here I'm touching both legs of the LED but nothing else:
EDIT: 1000th post!