I get the idea now. Thanks for the help guys.
840' of 30AWG enameled wire coming from Amazon now. Should be good for
a couple thousand turns.
On 11/3/2019 3:38 PM, ch...@wbmfg.com wrote:
This site shows the coil they are using. Lots of turns of small gauge
wire. The gauge is not important but the number of turns is.
https://www.sciencebuddies.org/science-fair-projects/project-ideas/Phys_p097/physics/high-speed-magnets-faradays-law-lenzs-law
*From:* Mark Radabaugh
*Sent:* Sunday, November 3, 2019 8:20 PM
*To:* AnimalFarm Microwave Users Group
*Subject:* Re: [AFMUG] OT: Induction coil voltage
An old motor or speaker will have a decent amount of enameled wire it
it that you can use. Scrape or melt the enamel off where you want it
to conduct.
Use two LED’s in parallel with the anode opposite directions and you
should get alternating lights when you shake it.
I wouldn’t worry about the meter - if it’s digital it will be too slow
to show you much.
Mark
On Nov 3, 2019, at 2:54 PM, ch...@wbmfg.com wrote:
The magnetic field from an electromagnetic is proportional to the
turns and the current.
So the inverse is also true. You have a fixed amount of magnetic
flux, the current will be proportional to the number of turns. It is
called the ampere-turns ratio. Lots of turns of 30 gauge will be
good. 30 gauge is common as it used to be used for wire wrapping.
Also make sure the magnet is oriented such that its field cuts the
coils at right angles. I would not worry so much about the voltage.
You want 10 mA if you can get it.
https://en.wikipedia.org/wiki/Ampere-turn
*From:* Adam Moffett
*Sent:* Sunday, November 3, 2019 5:51 PM
*To:* af@af.afmug.com
*Subject:* Re: [AFMUG] OT: Induction coil voltage
I'd bet I have 20-30 turns of 16ga wire....that's just what I
happened to find first. I could tear apart some CAT5 and use the
24ga inside so I can get more turns in the same area. Or I can find
something with a transformer inside and unwind the super skinny wire
on it. I just don't know to what extent I need to go to make this
thing work.
And yeah it's not obvious in the picture I sent, but you're supposed
to connect the two LED's together short leg to long leg so that one
of them lights up when you drop the magnet North first and the other
lights up when you drop it South first.
I'd wondered about the length of the pulse too. It's a cheapo
digital multimeter. It does not read the same on each drop of the
magnet. When I say it read 30mV that's just the highest number I saw
after several drops.
-Adam
On 11/3/2019 12:40 PM, Ken Hohhof wrote:
I would think yes, although it seems the electrical pulse will be
very brief and I’m not sure you’ll be able to measure it with a
meter. Also have you determined the polarity of the DC generated or
tried hooking up the LEDs both directions?
In any case, I’d think wrapping the entire length of the cardboard
tube with wire would make the LEDs light up for a longer time and be
more visible.
How many turns do you have on it now?
*From:* AF mailto:af-boun...@af.afmug.com *On Behalf Of *Adam Moffett
*Sent:* Sunday, November 3, 2019 11:20 AM
*To:* af@af.afmug.com
*Subject:* [AFMUG] OT: Induction coil voltage
I wanted to do this science experiment with the kids. My problem is
my LED's don't light up. It's from a discontinued textbook.
Apparently they sold a kit with the materials for all the projects,
but that's no longer available so I'm scrounging in the garage.
I put a volt meter on the rig and I was only getting 6mV when I
dropped the magnet. I doubled the number of coils on the tube and
then doubled the number of neodymium magnets and I'm getting closer
to 30mV now, but I need closer to 2V to light up an LED, so I'm
wondering what would increase the voltage by two orders of
magnitude. Is it based on the number of turns in the coil?
<image001.png>
------------------------------------------------------------------------
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
------------------------------------------------------------------------
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
--
AF mailing list
AF@af.afmug.com
http://af.afmug.com/mailman/listinfo/af_af.afmug.com
