Mechanical Resonance (Projects)

[Magluvin]

You're not the only one that got that idea!...  I ordered mine on the 13th and will have it on Monday: http://www.ebay.com/itm/131526761089

Unfortunately my time at the lab has ran out so it may be a while before I'm able to put the device together.

Luc

Cool. They are at a good price for testing them here.  Luc, always a step ahead of the crowd.

Mags

[Magluvin]

Maybe the travel will not be enough?
Maybe a magnet on a wine glass lol
Sorry,couldnt resist that one.


Brad

Thought about that. But may be good anyway. If higher freq increases the efficiency, smaller movement doesnt seem to be an issue.  As you have already shown compared to my 2.25 distance of travel of my mags. Will be interesting I think as we go along. It maybe a down the road we end up using quartz transducers from ultrasonic cleaners.

http://www.ebay.com/itm/40khz-35W-Ultrasonic-Piezoelectric-Clean-Transducer-Plate-Electric-Ceramic-Sheet-/221962064992?hash=item33adf85460:g:6jwAAOSwHQ9WZUE9

http://www.ebay.com/itm/50W-40KHz-Ultrasonic-Piezoelectric-Cleaning-Transducer-Ultrasonic-Cleaner-/291532940937?hash=item43e0b7a689:g:Ix0AAOSwjVVVwyJo

Still decent prices for experiments.

Mags

[gotoluc]

Cool. They are at a good price for testing them here.  Luc, always a step ahead of the crowd.

Mags

Yes, best price on ebay for that low a frequency.

Finding the most efficient way to make it ring with minimal input is obviously the most important part.
This will require many tests.
A physical electromagnet hammer, like the old bells used should be tested.
We also know that using a Tuned Resonator box will allow many tuning forks of the exact frequency to ring with no additional input.
If there's any possibility of extra power it will be from the freely Resonating forks. One hammered with no load and the rest Resonating with a load.

I've been wanting to try this for years!... but for now, one step at a time

Luc

[tinman]

@ Poynt--and all here interested.

Below is a few scope shot's in regards to holding the magnet still,and raising the frequency to see if there was a phase shift.

The first scope capture was taken at the resonant frequency of the oscillator,where i found the resonant frequency with the oscillator in play,and then stopped the oscillations.
The following two scope shots are at the higher frequencies with the oscillator stopped.
Please note the V/PD changes i had to make as i raised the frequency.
Even at 500Hz,i did not see much of a phase shift with the oscillator stopped.
CH1 is across the secondary /5 ohm resistor,and CH2 is across the 3 ohm CVR.
I do not know the dot convention,as the primary is sealed in apoxy resin,and i can find my compass.

In my next post,i carried out a small test that shows the bulk of the current in the secondary is being induced by the oscillating magnet.


Brad

[picowatt]

@ Poynt--and all here interested.

Below is a few scope shot's in regards to holding the magnet still,and raising the frequency to see if there was a phase shift.

The first scope capture was taken at the resonant frequency of the oscillator,where i found the resonant frequency with the oscillator in play,and then stopped the oscillations.
The following two scope shots are at the higher frequencies with the oscillator stopped.
Please note the V/PD changes i had to make as i raised the frequency.
Even at 500Hz,i did not see much of a phase shift with the oscillator stopped.
CH1 is across the secondary /5 ohm resistor,and CH2 is across the 3 ohm CVR.
I do not know the dot convention,as the primary is sealed in apoxy resin,and i can find my compass.

In my next post,i carried out a small test that shows the bulk of the current in the secondary is being induced by the oscillating magnet.


Brad

These captures appear to show the yellow trace leading the blue trace by 90 degrees (or lagging by 270).

What does it look like with the secondary unloaded?

I believe your secondary connections may need to be flipped...

PW