Creating inductors

[gastonanthony]

hey, we have that book in the school library, I'll check it out tomorrow, thanks

 

[chemelec]

get yourself a copy of The ARRL Handbook

Just for your info, They Publish a new ARRL Handbook Every Year or so. I have 2 Different editions, on of which is Quite Old (1969) and it is better on some info than My Newer 1993 Edition.

It might be worth checking out some Second Hand Book Stores for older editions. Cheaper Also.

 

[gastonanthony]

I'll try to do that too

 

[solidhelix]

OT:i try to charged an INDUCTOR (air core) with a 9Vdc and try to remove the 9Vdc source, this will generate a huge amount of voltage right? When i try to hold the terminals of the inductor i feel nothing...
The inductor's values is around 600uH based on the air core computation posted here...If the inductor will generate huge amounts of voltage i will something, right :?:

 

[Nigel Goodwin]

OT:i try to charged an INDUCTOR (air core) with a 9Vdc and try to remove the 9Vdc source, this will generate a huge amount of voltage right? When i try to hold the terminals of the inductor i feel nothing...
The inductor's values is around 600uH based on the air core computation posted here...If the inductor will generate huge amounts of voltage i will something, right :?:

It's rather a low inductance value, and presumably has a REALLY low DC resistance - I suspect it will short the battery out to the extent there will be hardly any voltage across it.

Try using a MUCH higher inductance, with a MUCH higher DC resistance.

A 1mH RF choke and a 6V battery easily light a neon bulb!.

 

[solidhelix]

OT:i try to charged an INDUCTOR (air core) with a 9Vdc and try to remove the 9Vdc source, this will generate a huge amount of voltage right? When i try to hold the terminals of the inductor i feel nothing...
The inductor's values is around 600uH based on the air core computation posted here...If the inductor will generate huge amounts of voltage i will something, right :?:

It's rather a low inductance value, and presumably has a REALLY low DC resistance - I suspect it will short the battery out to the extent there will be hardly any voltage across it.

Try using a MUCH higher inductance, with a MUCH higher DC resistance.

A 1mH RF choke and a 6V battery easily light a neon bulb!.

You are saying that i should use a higher inductance value? presumbably 1mh?

 

[Nigel Goodwin]

You are saying that i should use a higher inductance value? presumbably 1mh?

No, I would suggest you probably use a much higher value than that, but in particular you need a higher DC resistance - or it will just kill your battery. Using a transformer rather than a simple coil will help as well, the transformer action will step up the back EMF - just as a car ignition coil does.

I'm presuming you're just playing with a coil and a battery?, and not trying to make a switchmode PSU?.

 

[gastonanthony]

I think what he needs is a capacitor, or capacitor banks to store the charge and discharge it at a higher voltage level. Try a transformer, hold the 220 V and ground side with one hand and then on the other side, connect and disconnect the 9V battery, that would make you feel more than just something

 

[audioguru]

A relay's coil makes a pretty high voltage when the battery is removed and doesn't draw enough current to kill the battery.
What would the inductance be? 1H?

 

[solidhelix]

The relay coil did it

I did feel something :!:

I think what he needs is a capacitor, or capacitor banks to store the charge and discharge it at a higher voltage level. Try a transformer, hold the 220 V and ground side with one hand and then on the other side, connect and disconnect the 9V battery, that would make you feel more than just something

I think using a transformer will send me to the graveyard

I'm presuming you're just playing with a coil and a battery?, and not trying to make a switchmode PSU?.

Yes i was just playing around

 

[Nigel Goodwin]

I think using a transformer will send me to the graveyard

No, even a car ignition coil won't kill you, but it does make you jump :lol:

 

[gastonanthony]

yup, the kind of transformer i'm talking about is 220-12v, it doesn't hurt that much, it is just a bit of a shock at first, but soon you'll get used to that little amount of current

 

[williB]

just a little side note on the Topic ..
i took apart a ferrite core inductor recently..
and i found that they had made the main wire out of a bunch of little strands and wrapped them with silk for insulation..
it was a pretty smart way to do it..because with just one wire i am sure they would have needed many more turns to get the same inductance ..
but by breaking the wire into smaller strands i am sure the electromagnetic effects were increased..

 

[Nigel Goodwin]

just a little side note on the Topic ..
i took apart a ferrite core inductor recently..
and i found that they had made the main wire out of a bunch of little strands and wrapped them with silk for insulation..
it was a pretty smart way to do it..because with just one wire i am sure they would have needed many more turns to get the same inductance ..
but by breaking the wire into smaller strands i am sure the electromagnetic effects were increased..

I don't think it increases the inductance?.

It's basically a type of 'litz' wire, but I don't think 'skin effect' is the reason for it's use - I suspect it's mostly to give a high current capability wire that's flexible enough to wind.

 

[Miles Prower]

It's basically a type of 'litz' wire, but I don't think 'skin effect' is the reason for it's use - I suspect it's mostly to give a high current capability wire that's flexible enough to wind.

Litz wire does have the advantage of increasing the Q of a longwave coil by reducing AC resistance. However, it only works at sub-MHz frequencies since a high frequency tends to propagate by jumping across the strands instead of following each one.