Hey, popi, too much mathematics for an audio forum. I´m become crazy, ja ja ja!
Hi Osvaldo, sorry, but some things, I don't know how to say.
NOMEX, ε = 1.6 (for a thickness of 0.08mm)
Kapton, ε = 3.9 (for a thickness of 0.08mm)
C = (ε A) / (4πd)
It is better if you do 3P's and 4S's where you start and end with a S. The first and last S's will have half turns compared to the inner sections. In this way the f.e.m. will be preserved. Otherwise the f.e.m. will be distorted to some degree. This happens because the inner S section "sees" two P's instead an outer S section will only "see" one P (on one side only).
Of course you can do 4P's and 3S's if this comes better in a practical winding condition.
Yes can work, is Teflon, the only drawback is that it is too flexible.
Try this, finished the winding, wrap it generously with Teflon tape, above you put a layer of Mylar or paper, then when you make the next winding and the wire does not sink.
With a caliber, you can check the dimensions, to fit all the wire into the window.
Almost forgot, before using Teflon/Mylar/etc., place it in a microwave oven, to ensure that no scrap metal, if it make fireworks, then do not serves.
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The yellow is for gas lines.
http://www.grainger.com/Grainger/ANTISEIZE-Gas-Line-Sealant-Tape-4UK07?Pid=search
http://www.grainger.com/Grainger/ANTISEIZE-Gas-Line-Sealant-Tape-4UK07?Pid=search
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I think the purpose of the tape is more for reduction of inter-layer capacitance than as a dielectric.
Since I'm considering bi-filar winding, it probably matters very little other than providing mechanical insulation to prevent overlapping windings from creating pressure points that could result in breakdown and shorting of turns.
Since I'm considering bi-filar winding, it probably matters very little other than providing mechanical insulation to prevent overlapping windings from creating pressure points that could result in breakdown and shorting of turns.
Inter-layers acts as a dielectric and as an insulator, inter-windings acts as a dielectric and as an insulator, but the voltage between windings is greater than between layers, be in mind that secondary is at a potential near ground.
If the Teflon used in plumbing is like a sponge, let's advice to the plumbers.
Try to make bifilar windings, in this case, each layer must do left to right (or vice versa) always in the same direction of rotation, so that between each end have the same voltage between layers, then the capacitance will decrease.
BTW. Be careful with the wiring in this scheme.
Too many turns. IMHO.
If the bandwidth not exceeding 10 kHz, reconsider interleaving.
That 5 X Rp calc comes from RF practice when doing broadband coupling xfmrs. I've done a lot of these, but only for high frequencies where getting the necessary inductance is easily accomplished with a single layer (bifilar, trifilar, multi-filar) winding on a toroidal core. Audio frequency ISTs bring in a whole bunch of extra considerations.
Take a look at TV vertical deflection triodes. These types have nice, low Rp's, and some also come in dual designs incorporating a higher gain, small signal triode. These being designed for use as combination plate coupled multivibrators/deflection finals.
poplin, winding in the same direction is what I suspected as q=CV^2.
if all turns were wound in the same directions, the voltage difference between windings in one layer over the next remains constant across the layer.
When wound l-r then r-l, the winding at the right end of the first layer is at the same voltage (V) as the the first winding in the second layer. However, the first winding in the second layer is at 2V referenced to the first winding in the first layer.
Miles, thanks.
if all turns were wound in the same directions, the voltage difference between windings in one layer over the next remains constant across the layer.
When wound l-r then r-l, the winding at the right end of the first layer is at the same voltage (V) as the the first winding in the second layer. However, the first winding in the second layer is at 2V referenced to the first winding in the first layer.
Miles, thanks.
No, always capacitance is given by
C = q/V ==> q = CV
Considering what you mean by "same direction", this is correct.
If you are determined to do bifilar windings, note that between both wires will have almost the plate voltage.
Take a look on the datasheet of the wire for voltage breakdown.
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