Selfrunning cold electricity circuit from Dr.Stiffler

[derricka]

@all :

Second question is this : I have two digi-meters and each measures a different hfe-value. e.g. one shows hfe 100 the other hfe 120 for the same transistor.

Is there a standard-method of this hfe-measurement ? I do not trust these meters after this experience.

best Regards

Kator01

Hi Kator,
I suspect most typical low cost DVM's arn't properly calibrated when it comes to transistor measurement. Cheaper meters often only report Beta. (DC current gain)
Also, hfe comes in different types. (hfe is one of a suite of h parameters and refers only to the common emitter configuration. You can call it the AC current gain.)
Lower case is used to denote small signal operation. (hfe)
Upper case is used to denote large signal conditions. (hFE)
Small signal means signal is not large enough to take the transistor where the characteristics are significantly changed.
Large signal obviously does and is what you need for switching as the transistor will go from full off to full on. (Saturation)
hFE is always less than hfe.
Beta is a static (DC) parameter the DC current gain,which gives a rough idea of the ac gain.
Finally, hfe and hFE gains diminish at higher frequencies due to  Miller capacitance.

Hope this helps.

Derrick

[Kator01]

Hii Derricka,

thank you for your explanation. It is now clear that these dc-hfe-values are of no meaning, so I have to set up a circuit by which I will measure amiplitue, puls-response-time and dv/dt using a contant voltage-supply in two variations at a given frequency ( 5 to 10 MHz in this case as this is the range of operation in the ESEC)  :

1) contant-current-control
2) no contant-current-control

By comparing these two wave-forms I will get better data.  But again I would expect drstiffler do give us a hint.


Regards

Kator01

[DrStiffler]

@all

WHAT? has has taken place here, the overunity.com is now full of politics and .........

Where are the real people going to?

I will not post here.............

[AbbaRue]

@DrStiffler
There is a lot going on at the Joule Thief thread and it has a lot to do with your circuit too.
Check it out, so far it has been going very well.  (no negative vibes)
Maybe some of your experience could be helpful there too.
These units can be built from a disposable camera circuit.
So anyone can build one in minutes.
I strongly believe it can be modified to duplicate your cold electricity results.

[Pirate88179]

Dr. Stiffler:

Yes, I agree.  There is a good group of folks over there and everyone sticks to the experiments and no politics.  I have learned a lot since starting this topic and even with what little I know about how your devices work, I can see a relationship in that I can light 100 LEDs from an old AA battery with only 1 wire attached. (and 400 using both wires)  Please join us there as we would value your input.  Thanks.

Bill