RESONANCE EFFECTS FOR EVERYONE TO SHARE

[DrStiffler]

@Luc

You have some people giving some good solid information and methods (math) to figure out and present what you have. I would like to add a point that none engineers sometimes don't even think of and that is a resistor is not a resistor. Unless you use carbon resistors at fairly low frequencies you have to include their other characteristics in the computations. These power resistors very all over the place on inductance. I have for example included a picture of a 10ohm 25W resistor being measured at close to 750kHz.

This fact may be of interest to some and should be to all that include them in RF circuits.

[watercellguy]

Hi everyone,

I just uploaded a new video and would like everyone who can check to see if my way of calculating the power is correct.

Please post your comments

Link to video: http://www.youtube.com/watch?v=-P8zch1De-Q

Thanks for your time.

Luc

Luc,

1st I want to say great videos you have been doing.

Now about the calculations, from personal experiency, measuring power in VS power out using a resistor in series with the input circuit and a resistor in parallel with the output circuit will allways misslead you to OU.

I attached a snapshot that shows what I'm talking about. The top scope graph shows the voltage accross the output resistor and the bottom graph shows the voltage accross the input resistor, it clearly shows that this method of comparing power in VS power out is incorrect.


Now I'm not an EE, but I think the reason for this, it is because measuring it like this does not take in consideration for the inductor/capacitor reactance and in this case it is about 316 ohms for the inductor and 316 for the capacitor at 50.3 Hz. So I'm thinking if we use resistors that match the reactance resistance, then we could get acurate readings.

I also have been testing resonance circuits and have not yet verified OU.

[AbbaRue]

@gotoluc
What appears very interesting in your setup is each coil is actually a step down transformer.
Am I seeing right?  Are those secondary windings made of only a few turns of thick wire?
Could you give us the figures of how many windings the primaries and secondaries are?

[jadaro2600]

Hello all,

It occurs to me that if you want to have a resonant circuit, it must be 'annoyed' into producing usable energy - in other words, it must want to do work through sound, light, heat or motion or some combination thereof rather than ground out.  It should work in the same way that a simple radio works ( but without being grounded )

It also occurs to me that when you ground something, chemicals in the soil may be producing a net electrical difference through differential metals and extraordinarily small currents or voltages should be accounted for and negated when taking measurements.

So doe the resonant effects have anything to do with simplistic radio or am I wrong?

- - -
I've been looking over this thread, and it appears that none of the devices built and shown should ever be taken near an airport - they all look like pipe bombs.

[gotoluc]

@Luc

You have some people giving some good solid information and methods (math) to figure out and present what you have. I would like to add a point that none engineers sometimes don't even think of and that is a resistor is not a resistor. Unless you use carbon resistors at fairly low frequencies you have to include their other characteristics in the computations. These power resistors very all over the place on inductance. I have for example included a picture of a 10ohm 25W resistor being measured at close to 750kHz.

This fact may be of interest to some and should be to all that include them in RF circuits.

Hi Dr. Stiffler,

thank you for taking the time to share this very valid and valuable information. As I said above I was not happy with my attempt to measure the coil efficiency, so I made a new video and I would ask for you to look at it to see if you agree with this way of calculating the performance output of each coil. I do believe the use of the 10 ohm resistor as load on each 30,000uf cap is accurate enough since that large cap size should be more than enough to smooth it to DC. After doing the video and seeing your post I attached the probes to one of the coil output cap and I attached the scope shot below. Looks fairly flat to me and I am also happy to report my meters are accurately displaying the volts the scope is displaying.

The only thing I can see where there may be a problem is the 10 ohm input resistor. The frequency at this time is 300Khz, do you think if I pickup a accurate carbon resistor we could measure to a satisfactory result?

Link to new video: http://www.youtube.com/watch?v=ylnH1-UGITE

Thank you for sharing

Luc