inductor questions

[Eric R Snow]

The Jameco catalog doesn't have any inductors that are 1000
micro-henrys. Only less. Can these be connected in parallel or series
to increase the inductance? Or is it easy to wind my own accurately?
How can the inductance be measured? I have a Tek 465B 'scope but I'm
still learning how to use it and don't know if it can be used to
measure inductance.
Do I need a ferrite core? I have a machine shop so making the
mechanical parts to wind coils is easy for me.
Thank You,
Eric R Snow

 

[Activ8]

On Mon, 02 Aug 2004 14:55:02 -0700, Eric R Snow wrote:

The Jameco catalog doesn't have any inductors that are 1000
micro-henrys. Only less. Can these be connected in parallel or series
to increase the inductance?

Series, but check Mouser and I forget who else I've ordered from.

Or is it easy to wind my own accurately?

Could be.

How can the inductance be measured?

With a Dip meter or inductance meter.

I have a Tek 465B 'scope but I'm
still learning how to use it and don't know if it can be used to
measure inductance.

It would just be acting as a volt meter.

Do I need a ferrite core?

Probably. It would lower the turn count but without knowing your
application I can't say.

I have a machine shop so making the
mechanical parts to wind coils is easy for me.

Great. I'll do your electronics and you do my machine work

Thank You,
Eric R Snow

--
Best Regards,
Mike

 

[John Popelish]

Eric R Snow wrote:

The Jameco catalog doesn't have any inductors that are 1000
micro-henrys. Only less. Can these be connected in parallel or series
to increase the inductance? Or is it easy to wind my own accurately?
How can the inductance be measured? I have a Tek 465B 'scope but I'm
still learning how to use it and don't know if it can be used to
measure inductance.
Do I need a ferrite core? I have a machine shop so making the
mechanical parts to wind coils is easy for me.
Thank You,
Eric R Snow

Digikey sells lots of inductors in the 1000 uHy and above range. The
other critical specifications for any inductor are the current rating
(both thermal and core saturation may be involved), the self resonant
frequency (above which, it looks like a capacitor, instead of an
inductor), the DC resistance (affects the heat it produces) and the
effective Q (quality factor) at a given frequency, if you are going to
use it in a tuned application.

Inductors are one of the few kinds of components you can mak,
yourself, that rival the quality of what you can buy. You will need
enameled wire of the appropriate size, and ferrite or powdered cores
and possibly plastic winding bobbins. The cores and bobbins are what
are hard to find. But some are available. For radio frequency
inductors, you often need only a form to hold the wire, with air
making up the magnetic field path. The whole story is more than I can
put in 1 post.

The best way to measure inductance is with a meter made for the
purpose, but all sorts of inductance bridge measurements are possible
that include a scope or meter as a magnitude and/or phase display that
you watch while you null the bridge with known components.

--
John Popelish

 

[BobGardner]

How can the inductance be measured?

Resonate against known value cap. f=1/2*pi*sqrt(LC)

 

[Richard]

John Popelish <jpopelish@rica.net> wrote in message news:<410EE0AD.B305A0A3@rica.net>...

Inductors are one of the few kinds of components you can mak,
yourself, that rival the quality of what you can buy. You will need
enameled wire of the appropriate size, and ferrite or powdered cores
and possibly plastic winding bobbins. The cores and bobbins are what
are hard to find. But some are available. For radio frequency
inductors, you often need only a form to hold the wire, with air
making up the magnetic field path. The whole story is more than I can
put in 1 post.

Funny, I still have an "Allied Radio Corp" coil calculator (paper
slide rule) for dimensions so you can wind your own RF inductors.
From high school days, back when we had to walk 10 miles through chest
deep snow to get to school...
Richard

 

[Tom Biasi]

"Richard" <beezoboar@hotmail.com> wrote in message
news:9fa77d4c.0408240515.24b0d7d3@posting.google.com...

Funny, I still have an "Allied Radio Corp" coil calculator (paper
slide rule) for dimensions so you can wind your own RF inductors.

From high school days, back when we had to walk 10 miles through chest
deep snow to get to school...

Up hill both ways?

 

[Rich Grise]

Tom Biasi wrote:

"Richard" <beezoboar@hotmail.com> wrote in message
news:9fa77d4c.0408240515.24b0d7d3@posting.google.com...

Funny, I still have an "Allied Radio Corp" coil calculator (paper
slide rule) for dimensions so you can wind your own RF inductors.


From high school days, back when we had to walk 10 miles through chest
deep snow to get to school...

Up hill both ways?

You had snow? We had to swim through the magma that was yet to become
crust...