Interesting experiment with an transformer, 2 lamps, diodes and an magnet

[gast]

Hi,

this evening I made an interessting experiement with an sqaure wave generator, an self-wounded 1:1 transformer on an toroid core, some diodes and two lamps. And of course an magnet. (steven marks keeps my mind busy ;-) )

The primary side of the transformer is powerd by the sqare wave generator, at the secondary side of the transformer I connected an 6V lamp. On the primary side of the transformer I connected a second 6V lamp but using an diode, so that the lamp is powerd only by the kickback from the primary coil!

Then I swiched on the corcuit and tuned the the genrator to a level, the lamps light middle-bright. Now I took the magnet and near(? german: ann?hern) it slowly to the toroid core (the exact point of the core is important, also the winding, I think).
The result: Depending on wich side of the magnet I near to the core the following things happend:

1) The light of the normal powerd lamp becomes a bit brighter, the other kickback powerd lamp a bit darker, but the power consumption of the circuit increases rapidly.

2) Using the other sinde of the magnet. The light of the kickback powerd lamp becomes a bit brighter, the other normal powerd lamp a bit darker, but the power consumption of the circuit **decreases** by more than 1/3.

Hmm, I think I have to make a draft of the circuit the next days.

Sorry for the syntax-errors... its late and I my cheap internet connection ends in a few minutes...

Regards, Gast

[hartiberlin]

Hmm,you probably change the working point of the transformer on the BH curve,
so what you do it impedance matching somehow...

Only via real numbers( power measurements) more can be said, which is complicated,
cause it is AC and the phase angle must be measured in and also the kickback energy
in the Back EMF spike...

Regards, Stefan.

[gast]

Hmmm, unfortunately I still doesn't own an scilloscope or any other hightech equipment.

I measured the amperes direct on the battery in DC mode. But even if the circuit sucks pulsed DC and the voltmeter does't show right values, the measurement-error should be the same in both configurations, because I doesn't changed the frequency of the generator. If I find the time, I post a draft this evening.

What is about the following way for power-comparing (okay it's more an estimation)?
I would connect a big buffer capacitor to the whole circuit and measure voltage and ampere (DC) for the complete circuit including the lamps. I will do this using the magnet and notice the brightness of the lamps (over my big thumb ;-)).
After this I would measure voltage and ampere without the magnet but adjusting the frequency to a level where the lamps have (subjective) the same brightnes like in the other configuration. Then I have to compare the values. Are the values compareable this way?

Regards, Gast

edit:
PS: What's about using a combination of a rectifier and a load instead of the lamps? On the load I can measure the DC voltage and ampere. So I have not to handle with AC and phase angles.

[gast]

Stefan,

now I made some pictures and videos from mysetup.

Please, would you have a closer look at it to decide if it is only a imedance modification or not.

You'll find a shematic/draft of the circuit and some pictures of the setup and the toroid ferrite-core.
Further I recorded two videos showing the effect. The first video is made with room light switched on, the second one with room light switched off for a better recognizing of the change of brightness by the kickback lamp.

Some remarks:
- Please notice that the brightness of the kickbacklamp (the upper lamp in the video) becomes much more brighter than the normal lamp becomes darker. The ampere-consumption (DC-mode) decrases nearly to 1/2.
- Without magnet I never get the kickback lamp so bright, regardless of the frequency I tune on the generator. Okay, If i tune up and down, then there is a small point where the lamps are really bright. But this point is NOT stable. Its more like an short flash during frequency tuning.
- The wooden stick and the lighter on/besides the core is only used to hold the correct distance between magnet and core. The neodym-magnet is much to strong! If it snap direct at the core (*click*) the lamps goes off and the ampere-consumption increase rapidly. The best distance for this magnet is about 1,5 cm from the core. If I move the magnet more near than 1,5cm the ampere consumption begin again to rise.
- The multimeter showes ampere in DC mode. There is no buffer capacitor. So depending on the condition of the battery the multimeter measured pulsed DC.
- the winding orientation of the priimary and secondary coil is not equal, it is oppositional (the coil-orientation painted in the draft is wrong).

I would be happy about some suggestions.

Bye, Gast

PS: I get several errors during sending this message incl. the 9MB zip-file. I send the attachment via mail to stefan.

edit: I'll try to attach only the pictures, maybe I will get no errors this time... (videos are allready sent to Stefan)

PS2: Today [08. Sept 2005] I modified the setup a bit for another test: I changed the toroid core and the normal powerd lamp against one normal coil on a ferrit rod (1,6 mH) - no normal lamp this time. The kickback powerd lamp lights up after switching on the circuit. And I was also able to incrase the brightness of the lamp by moving the magnet near to the ferrit rod. But independent of the polarization of the magnet the lamp became always a bit brighter BUT the ampere consumption arised in every case! I never was able to decrase the ampere consumption with this configuration (unlike to the setup with the toroid core and the 2 coils on it).

Is this remarkable?

[hartiberlin]

Here is video 1 fromMarkus, converted to a smaller MPEG4- Microsoft V2 codec
which is more compatiblewith older systems and also 1/4 the size.
As there was no speech on the audio, I deleted the  audio part as it contained
only noise... Better Markus next timeyou speak to the video, what you are doing..