From: Paul
Date: Sun, 07 Jan 2001 20:36:07 +0000
Subject: Re: [TSSP] L measurements
Metlicka Marc wrote: > > paul, > these were all taken with the coils in free space, actually setting > on my milk crate but nothing but carpet and floorboards beneath. > also i moved everything so that the area surrounding the coils was > removed, a good 7' of free space all around. i will say that the walls > are of the chicken wire rock lath type. all measurements were made after > i checked the inductance's of the leads shorted together and the > resistance's of the leads subtracted. my manual actually states to use > twisted pair leads for high accuracy in L readings, so i did. all L > readings were using the 1 khz internal generator. That sounds like a first class measurement. The #3 L calculated on the basis of 3001 turns (turns counter) comes out at 386.5 mH, and the resistance is 454 ohms, so I wonder if somehow you have fewer turns to obtain 355.5 mH and 425.8 ohms. Seems to me that counting turns along a secondary would be a straightforward job for software. Take a line of pixels along the coil and convert to the spatial frequency domain, and then look for the whopping spike in the spectrum. Somebody ought to write a little utility program. BTW, I take it the 'Q' readings accompanying your data apply to 1kHz, I hope so! Cheers, -- Paul Nicholson, Manchester, UK. --
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.