[Lowfer] Coil question???

[Mitch Powell]

Mike:
I wound that same coil last week - following ideas from Dex's pictures.
With 18 inch diameter, I used #14 plastic covered household wiring. I
Had 11 vertical 3/4" PVC pipes and did a basket weave.
Coil was 70 turns - height was 7 inches. Inductance measured on Boonton
Q meter was 2.4 mH and Q >400. I couldn't come within 2 feet without
changing the resonant frequency.
Then used a plastic pail to wind a variometer - 10 inches diameter, 4 inches
high, close-wound - same #14 plastic covered wire.
Can tune from 2.3 to 4 mH.  or over the entire 160-190 kHz range.

Calculated all these values with Bill Bower's formulas, and was within a
turn in each case - great stuff !

Hope this helps.

73
Mitch VE3OT