Falcon MD20

[WM6]

Think I was a bit unclear, the coils inner must be 9,7 or like 10mm because the ferrite rod is 9,7mm thick. Or am I thinking wrong, what would the winding be if the coils inner diameter is 10mm?

My calculations was for air core coil.

In case of ferrite core there is no calculator as correct KT315 say, cause ferrite rods characteristic are uneven.

With ferrite you need other approach, by examination test, but you need inductance meter.

First you need to wound some testing turns of wire on your ferrite: say 30 turns or so (more turns more exact results at the end).

After testing coil (of say 30 turns) is wound, you need to measure its inductance.

If your testing coil of 30 turns has measured inductance of (say) 20uH, then you need per 1uH (30/20=1.5) 1.5 turns of wire.

According given results, you need for 140uH (140x1.5=210) 210 turns of wire (210 in this example approach of course).

[Qiaozhi]

Try this ->

http://coil32.net/ferrite-rod-core-coil.html

[kt315]

If coil inner diameter is 5.1mm (9.7 - (2.3+2.3) = 5.1) and wire gauge AWG32 (0.20mm),
then to get inductance of about 140uH you need about 1040 turns.

is the FERRITE rod diameter (only ferrite) 5 mm? i did calculate for 9.7.
i tell again - NOWHERE is a calculator for a coil with ferrite. you have to take 100uH approx value.

[Friiman]

Think I was a bit unclear, the coils inner must be 9,7 or like 10mm because the ferrite rod is 9,7mm thick. Or am I thinking wrong, what would the winding be if the coils inner diameter is 10mm?

[Friiman]

Thanks a lot, that gave me an idea to make the coil.
Nice finding someone who can answer this questions.
So now I will order som wire and see how it goes

[Thomas]

http://coil32.net/online-calculators/multilayer-coil-calculator.html

[WM6]

If coil inner diameter is 5.1mm (9.7 - (2.3+2.3) = 5.1) and wire gauge AWG32 (0.20mm),
then to get inductance of about 140uH you need about 1040 turns.

[kt315]

i do not see on-line calculator for a coil on ferrite rod, as there noticed it is hard to calculate. so i did calculate without
ferrite. it give me 80-90 turns for 100 uH - i decrease 150 to 100 because ferrite increases the L value.
so you may wind same and after measure, then wind off turns step by step while you would get this 140-150uH.

[Friiman]

Think it´s 0.20mm wire, showing 0.22mm.
Its hard to measure so tiny wire when i cant grab it so good.
Need to calculate the coil winding now, not my best skill. But there is plenty calculator for it, but i dont know how to enter the information to get it to show 140 or 150uh and the resistance at about 2ohm
Somebody know how to make the search coil?

[kt315]

can you measure the wire diameter?

[Friiman]

Thanks
I used a digital slide guage and it showed this
diameter is 9,7mm
length is 50mm
and the coil show about 2,3mm thick and about the same in height

[kt315]

how much is diameter of ferrite rod and lenth? good home work, thanks.

[Friiman]

Does anyone know how many turns o wire and size etc? would help alot thanks =)
Hope you can manage to figure out my remake of the board

[Friiman]

[Friiman]