Does anyone know the formula for figuring the number of turns necessary for a coil of a specific inductance?

I have a GE AM/FM radio with an open inductor in the FM oscillator ckt. Happily, it has the value, .47uH, printed on it. I took the ceramic core of the bad inductor and wound about 10 turns of insulated wire around it and it works ok. But it got me thinking.

My old theory book from the late 60's had all the formulas for inductance, but I tossed it thinking, when will I ever need this. About four years later I became interested in tube radios again.

So, here I am looking for a formula.

Of course, the moral of this is, never throw anything away.

Thanks.

If you google "inductance formula" you will get multiple hits. Some of the sites will calculate for you when you input your variables.

MRO

:Does anyone know the formula for figuring the number of turns necessary for a coil of a specific inductance?
:
:I have a GE AM/FM radio with an open inductor in the FM oscillator ckt. Happily, it has the value, .47uH, printed on it. I took the ceramic core of the bad inductor and wound about 10 turns of insulated wire around it and it works ok. But it got me thinking.
:
:My old theory book from the late 60's had all the formulas for inductance, but I tossed it thinking, when will I ever need this. About four years later I became interested in tube radios again.
:
:So, here I am looking for a formula.
:
:Of course, the moral of this is, never throw anything away.
:
:Thanks.

Mike M.,

One good place is at:

http://www.crystalradio.net/professorcoyle/index.shtml

Radiodoc
********

:Does anyone know the formula for figuring the number of turns necessary for a coil of a specific inductance?
:
:I have a GE AM/FM radio with an open inductor in the FM oscillator ckt. Happily, it has the value, .47uH, printed on it. I took the ceramic core of the bad inductor and wound about 10 turns of insulated wire around it and it works ok. But it got me thinking.
:
:My old theory book from the late 60's had all the formulas for inductance, but I tossed it thinking, when will I ever need this. About four years later I became interested in tube radios again.
:
:So, here I am looking for a formula.
:
:Of course, the moral of this is, never throw anything away.
:
:Thanks.

Thanks guys. Just what I needed.

:Mike M.,
:
:One good place is at:
:
:http://www.crystalradio.net/professorcoyle/index.shtml
:
:Radiodoc
:********
:
::Does anyone know the formula for figuring the number of turns necessary for a coil of a specific inductance?
::
::I have a GE AM/FM radio with an open inductor in the FM oscillator ckt. Happily, it has the value, .47uH, printed on it. I took the ceramic core of the bad inductor and wound about 10 turns of insulated wire around it and it works ok. But it got me thinking.
::
::My old theory book from the late 60's had all the formulas for inductance, but I tossed it thinking, when will I ever need this. About four years later I became interested in tube radios again.
::
::So, here I am looking for a formula.
::
::Of course, the moral of this is, never throw anything away.
::
::Thanks.