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I wound 2 inductors with similar wire (22 AWG, copper). They have 25 turns each. The cores I bought are similar.

2 inductors

One inductor has a value of 1.8 mH and the other one has a value of 3.7 mH:

Values

What's going on here?

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    \$\begingroup\$ How "similar" are the cores? \$\endgroup\$
    – tobalt
    Feb 25, 2023 at 11:36
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    \$\begingroup\$ The datasheet of the core should provide a tolerance value. If there isn't, or if there isn't even a datasheet..There is your answer. \$\endgroup\$
    – tobalt
    Feb 25, 2023 at 11:44
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    \$\begingroup\$ @S.Goswami Is it possible both have vastly different composition even though it should be same? - If it happens, it must be true! You might hope for better than 2:1 from the same batch - but - some cores are low permeability designed for consistency, and other cores are high permeability, where high means 'as high as possible', and you get what you get as long as it exceeds some threshold. Sounds like you have the second type. \$\endgroup\$
    – Neil_UK
    Feb 25, 2023 at 11:44
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    \$\begingroup\$ I count 26 turns \$\endgroup\$ Feb 25, 2023 at 11:51
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    \$\begingroup\$ I hope you don't intend to run any DC bias through those. They're high permeability ferrite cores, they'll saturate right about 1mA. With A_L = 2.7 to 5.5 uH/t^2, and guessing from the wire size these are T50-ish parts (12.5mm OD?), permeability seems to be 10k-21.6k, quite high, but within reason for ferrite. \$\endgroup\$ Feb 25, 2023 at 14:53

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