Thread: Eric Dollard
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Old 08-02-2012, 11:49 AM
Nhopa Nhopa is offline
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Join Date: Nov 2011
Posts: 134
Coil tuning

Hi dR-Green:
Thank you for the response. I will eventually do the suggested tests but first I want to find out what is the best wire spacing on the secondary for max frequency response. Second, I will build a new extra coil using #13 AWG in lieu of #25 AWG. The problem with holding the can and the meter is that it do influence the readings, but I have to have short leads from meter to ground and between meter and can in order to minimize their contribution to capacity. I noticed even my body's proximity to the test set up influences the readings, so normally I have to step back after frequency adjustment to see that the meter stays at that maximum. One would need a real laboratory setup to do these tests properly. Who would have thought that Eric's simple CRI sketch would require so much effort to be successful.
If I use a shortened version of the extra coil, i.e. connect at the 49.5 m point then I do get resonance at 1,186 Kc (pretty close to my target 1,188 Kc) with the condenser rings 64 mm apart. Are you suggesting to tune the secondary coil with a full length extra coil for 1,188 Kc by adjusting the rings' spacing?

P.S. Comments from Eric or any of the other builders also welcome, except I know currently we lost Eric to the wilderness.
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