I am wondering if it's possible to build a mechanical version of the thing
they call a "Joule Thief"
What is a Joule Thief?
It takes a low voltage that is too low to light up a bulb
and it transforms it through a
coil and makes it into a high enough voltage to light the bulb
That's pretty much it. The question is,
can we do that mechanically so
Let's give it a shot. The main components of a Joule Thief
are: some souce of power,
a coil of wire and a light bulb that cannot be lit with the source of power
Usually the source power is about half what it takes to light the bulb. In this case I am using
a neon light which takes somewhere between 35 and
70 volts to turn on and we"ll try to turn on with about
15 volts instead. The coil of wire I am going to use, I'm not going to use this coil,
I'm going to use a coil of wire from a relay
and I'll show you why in a bit. I am going to use this coil of wire
and those will be our main components: power supply,
bulb and our coil of wire. Now let's do the next step
Let's show that this bulb will not turn on with the 15 volts
First attach 1 alligator clip
attach the other alligator clip and
no, nothing. How about if I try sparking it?
nothing
This bulb will light up orange when it goes on.
Next step, let's see if we can
power the bulb through the coil. Let me
og off camera and do the set up and I'll be right back.
Here's our setup. We've got the ground wire going to 1 side of the coil
The 2 yellow wires go to our bulb and the red wire
Let's see what happens when we
See that? Going through the coil
will allow us
to light up this bulb, not very long but it is lighting up
We have something that works a lot like the ignition coil on your car
Charging up the coil and then allowing it to discharge back through the
light bulb. We can get a little bit of transformation
The question is how do we make that run a little bit
longer-term. How do we turn it on
for a longer period of time? Let's try another experiment here
Same set up as before, coil
Wire are the same, but I added this highly scientific
pair of tweezers in the circuit
when I rub the clip on here
it turns it on and off very quickly and I if I could do this fast enough, long enough
I could probably keep that light bulb on
But I can't do that so
OK, we have shown that we can light up the bulb with half the voltage
If we could find a system that can do this
we could keep the light bulb on, but this not very convenient
Let me to make 1 more change to the circuit
and a we will see if we can't create
our ongoing Joule Thief, our "free running" joule thief.
Now what I have done is I have wired
he power to go through the relay
so that the relay will turn power on/off
for me and let's see if
if this will work. Get our lightbulb so we can see it.
There we go
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and there we have it. We have a mechanical version
of a ... Joule Thief.
Driving a neon bulb, 30-70 volts
with 14.9 volts input
So yes, you can have a mechanical Joule Thief
Hope you found it interesting