Rosemary Ainslie circuit demonstration on Saturday March 12th 2011

[Rosemary Ainslie]

Sorry Rosemary . Another Senior Moment there! This business of one cycle every 3 Minutes is just so Gobsmacking that my subconscious keeps trying to tell me its 3 seconds . This makes it even easier to drive the microswitch at realistic frequencies for experiment with a pendulum .Although at one cycle/3 minutes you would need one hell of a pendulum . As I said a while back you could actually switch it manually with a stopwatch .

LOL  I also took a day or two to realise that it was minutes not seconds.  And then only because it was pointed out to me by one of our academics.  Interestingly there is NO drop in temperature over the resistor.  Also - if you disconnect - for 3 minutes then the temperature drops dramatically.  It's not in the material of the iron.  So?  Here's the question.  How come the batteries are 'retaining  charge' and yet dissipating energy?   You see why it is that our academics are closing there eyes here?  LOL.

So glad we've got you to deal with the practicalities of this design Neptune.  I have no skills here - at all. 

Kindest as ever,
Rosie

added
BTW Neptune.  The ideal would be to get it to 'trigger' into oscillation mode and then just leave it to do it's thing.  No need for any further switching - I'd have thought?  It's holding the temperature - so it's doing work - and it's not - apparently, losing any charge at the batteries.  It would be a really good test - if you guys - someone?  can set this up.  I'm going to give it at go at this end but, because I'll be relying on others to do your circuit - then it'll take time. 

[neptune]

Hi Rosemary . Yes all points noted . If experiment shows that transients are necessary , and just switching on and off that 9 volt battery does not do the job , I would think the next step would be having two batteries each with its own pot and the hand operated microswitch idea . That way we have alternate pos and neg pulses on the gate , and we can adjust the voltages of the pos and neg pulses independently .When the oscillations start , just release the switch and it defaults to a steady neg condition . I am more of a practical guy than a theoretician  , but from reading the article about prevention of parasitic oscillation in parallel Mosfets , I get the impression that 2 is the minimum number of mosfets to use , But choose the value of your load resister so as not to draw more current than 2 mosfets can handle . Rose I understand you are waiting for someone to help set up experiments but I am sure we will get there soon.

[Magluvin]

So?  Here's the question.  How come the batteries are 'retaining  charge' and yet dissipating energy?   You see why it is that our academics are closing there eyes here?  LOL.



Kindest as ever,
Rosie

Could it be,  hmmm,  could it be that the heat created in the resistor is not really a loss felt by the batteries, and it is just an artifact of current flow.   If we think about it, as the resistor heats up, the resistance will become higher as the heat becomes hotter.  As the resistance becomes higher, and current becomes lower, yet the heat is higher.   More heat for less energy?

This was just a blurt.  I have to think about this.

Mags

[Bubba1]

Exactly my point Bubba.  vi dt.

vi dt is not power, it is energy. power is vi.

[Rosemary Ainslie]

Guys - there's someone contacted me who may be prepared to fund the required to take this to an application for LED's.  Neptune - if you're game - let me know - or anyone who wants to take this further.  It's nothing to do with me.  I'm just  go-between.  But if you're up for it. PM me and I'll send on the details.

Kindest regards,
Rosemary

Also possibly Mags, nul-points  - whoever.  It may be a way of getting this tested DIRECTLY onto a limited application.  And I'm sure that there'll be some compensation for the outlay.  Just let me know.  I'm back here later tonight or tomorrow morning early.  I like the thinking.  Just get it up and running and explain how it works after.  Something like that.  You'd be able to test the battery durations and the whole gamut.