I scanned the whole of that page but all references to "spoler" seem to have become "unspolen" Sorry indeed. Anyway, thanks for your swift reaction. I will see that this problem gets wound up again
Peter, An article called Low Frequency Coil Q, by Bill Bowers, is reproduced in the Low Frequency Experimenter's Handbook, Page 65 That's probably where I saw it, as I didn't belong to the LWCA back