Any experimenter that wants a quick and easy way to try out a cylindrical bifilar coil can simply buy a nice spool of fairly fine gauge speaker wire.  All that you have to do is make the cross connection and voila, you have a nice machine-wound tightly-packed cylindrical bifilar coil to play with.  Preferably it would be on a plastic spool and then you also have the ability to add a core if you want.

Quote from: MileHigh on April 15, 2017, 06:33:18 PM
....
You second question is strange, what's up with you?  When you pulse a bifilar coil what happens?  The response of the coil to a voltage pulse comes into play with an L/R time constant and all of that stuff that has been discussed in depth many times.

Well, MileHigh,  can a square wave be considered pulsing a bifilar coil?

Conrad nicely demonstrates in his videos, especially in Part 1 https://www.youtube.com/watch?v=fC84W0PIZoE
when he switches from pure sine wave to square wave at 4 MHz, the bifilar coil nicely responds to
that wave much the same way as it does for the sine wave and of course the output response is sine wave as expected.
It gives pretty good response even to subharmonic (1/3) square wave excitation as well.

Is this still a strange question? 

Gyula

Quote from: MileHigh on April 15, 2017, 06:41:07 PM
Any experimenter that wants a quick and easy way to try out a cylindrical bifilar coil can simply buy a nice spool of fairly fine gauge speaker wire.  All that you have to do is make the cross connection and voila, you have a nice machine-wound tightly-packed cylindrical bifilar coil to play with.  Preferably it would be on a plastic spool and then you also have the ability to add a core if you want.

But you will get very very small interturn capacitance that way because the conductors are too far apart, even in the finest plastic insulated speaker wire. As you have pointed out, the interturn capacitance is small anyway, even with close-wound enamel insulated magnet wire.

ETA: I just saw Mags's result so maybe. That's a lot of capacitance he reports with his plastic-insulated wire with relatively large interconductor spacing. I get 2.19 nF with the bifilar pancake coil I showed in the first DC resistance test video (between disconnected files) which has 58+58 turns of #27 magnet wire and 661 microHenry when files are serially connected in the TBF manner.  My calculator predicts a resonant frequency of 132 kHz for those values. We shall see, got to take dog to dogpark now.

Quote from: MileHigh on April 15, 2017, 06:20:41 PM
There are tons and tons and tons of mistakes made on this forum and sometimes some of them are completely and utterly idiotic.  And almost all the time nobody says a single damn thing.  I don't see you going after them and many times you are fully aware of them.  So don't give me your nonsense and get my message loud and clear.  You're are trying to preen and wank and say, "Look boys, I'm going to go after this guy and it's going to be sport."  And I don't make "lots of mistakes."  Get out of your BS spin zone.

Nobody wants your show, conduct yourself like a proper person.

Your coming up with 10ohm on conrads coils shows your inexperience with seeing such and making even an approximate determination of the resistance and it is far from showing that you are an authority in this area. Then you say that the difference between 10ohm and .4ohm doesnt make a difference anyway.  Run the sim and see how long it takes for the ring to die down in each example. Its a large difference and your assumption of 10 ohms then posting all the formulas trying to show big issues to prove your view against others views, then yeah, it should be pointed out that you are not producing accurate info in your argument. That 10ohms wastes a lot of energy in the circuit at a very unnecessary and unrealistic rate. 

So maybe, if i have to be blunt, just shedup.

Mags

Quote from: synchro1 on April 15, 2017, 04:09:39 PM
@Tinselkoala,

Acting like you knew something and then set out to deceive everyone is a lot less flattering then just admitting to your ignorance.

There is nothing in my posts to you that is deceptive or even wrong. It is just too bad for you that the same cannot be said for you. Your deceptions and ignorance are right there in your history of posts, for everyone to see.

And I see that you are trying to push your nonsense on my YT channel as well. Thanks for the thumbs-downs by the way... now I know I'm reaching my Target Audience after all.