Surprised by inductance reading

[smisco]

I'd guess maybe the cores are different. 2.3H for 5.5K turns sounds reasonable if there are steel slugs or screws present. 1.86H sounds reasonable for 7k turns if there is no core at all, or a very minimal core.

Good call Antigua---- I didn't even think about it---The 5500 turn coil had the slugs installed when I took the inductance reading and the 7000 turn coil did not. After pressing the slugs in place the 7000 turn coil now reads about 3.4H

[Antigua]

Both coils are humbucker bobbins with the same basic dimensions. One is wound with #42 plain enamel wire, a little over 5500 turns averaging 75~80 turns per layer--DCR around 4.3k----The other is wound with #43 poly wire , a little over 7000 turns at 95~100 turns per layer ---DCR around 6.9k ---I was thinking the coil wound with~7000 turns of #43 wound have somewhat higher inductance than the one wound with~5500 turns of #42. My meter shows the ~7000 turn coil at 1.86H and the 5500 turn coil at 2.29H, does this make sense?

I'd guess maybe the cores are different. 2.3H for 5.5K turns sounds reasonable if there are steel slugs or screws present. 1.86H sounds reasonable for 7k turns if there is no core at all, or a very minimal core.

[smisco]

The ac resistances at 120 Hz, measured simultaneously with the inductances, should be very close to the DCRs. Are they?

Yes, probably a little higher but not that much---

[Mike Sulzer]

This was measured with an Extech 380193 at 120hz---

The ac resistances at 120 Hz, measured simultaneously with the inductances, should be very close to the DCRs. Are they?

[smisco]

You need to measure at a low frequency, such as 120 HZ, and your meter has to be capable of giving an accurate measurement with a low Q coil.

This was measured with an Extech 380193 at 120hz---

[Mike Sulzer]

You need to measure at a low frequency, such as 120 HZ, and your meter has to be capable of giving an accurate measurement with a low Q coil.

Both coils are humbucker bobbins with the same basic dimensions. One is wound with #42 plain enamel wire, a little over 5500 turns averaging 75~80 turns per layer--DCR around 4.3k----The other is wound with #43 poly wire , a little over 7000 turns at 95~100 turns per layer ---DCR around 6.9k ---I was thinking the coil wound with~7000 turns of #43 wound have somewhat higher inductance than the one wound with~5500 turns of #42. My meter shows the ~7000 turn coil at 1.86H and the 5500 turn coil at 2.29H, does this make sense?

[smisco]

Both coils are humbucker bobbins with the same basic dimensions. One is wound with #42 plain enamel wire, a little over 5500 turns averaging 75~80 turns per layer--DCR around 4.3k----The other is wound with #43 poly wire , a little over 7000 turns at 95~100 turns per layer ---DCR around 6.9k ---I was thinking the coil wound with~7000 turns of #43 wound have somewhat higher inductance than the one wound with~5500 turns of #42. My meter shows the ~7000 turn coil at 1.86H and the 5500 turn coil at 2.29H, does this make sense?