Original poster: Jim Lux <jimlux@xxxxxxxxxxxxx> At 03:02 PM 1/8/2007, Tesla list wrote:
Original poster: "Gav D" <gdingley@xxxxxxxxx> Hi all, I have been reading the Medhurst paper from which the much used coil self-capacity formula originates and noticed a formula for dielectric loss. Using this formula and calculating skin-effects, I have found that the PVC pipe often used for winding a secondary contributes more to reducing Q-factor than the conductor itself; I am correct?
PVC isn't all that lossy at a few hundred kHz. There is a loading effect from the dielectric, but that just increases the parasitic C, lowering the self resonant frequency. I would imagine that resistive losses still dominate.
I would appreciate your comments, Regards, Gavin