Electrical Faux Pas

[Evil Roy Slade]

@wattsup

Remember what zpe said in an earlier post. The transistor is a CURRENT controlled current source.

When you apply a voltage to the base the current will flow according to the resistive load on the base and emitter.

This is VERY simplistic but use Ohm's law to calculate the current. Things get complicated if you include threshold voltages, ac voltages, capacitance and inductance etc. Ignore these for now cos it will just make your head hurt.

The current will then be amplified (if it can) by the transistor gain, say 100 times.

That current will then be flowing through the bulb.

Again use Ohm's law to calculate the resulting voltage across the bulb. This voltage CANNOT be greater than the power supply voltage.

All devices have voltage and current ratings on them. If you exceed these ratings expect failures.
Analogy: The human body was not designed for unassisted flight. Therefore, jumping off the top of a skyscraper will result in a distinctly unhealthy outcome.

Learn these laws: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmlaw.html#c1

Use these laws to calculate expected voltages and currents BEFORE applying power and you will find that more of your devices will live to work another day!

Enjoy!

ERS

[wattsup]

Thanks alot ERS for that and also for your other post in probable anticipation of what I was going to ask next, which I did not have to.

If by chance you or z_p_e stumble on the Mini TPU thread, I asked for any EEer to possibly give their explanation on how the EM circuit is working and actually "when" it is activating the transistor in that circuit. It is located here;

http://www.overunity.com/index.php/topic,3599.msg63912.html#msg63912

Thanks again. Transistors are getting clearer and I have done some experiments last night without blowing any. I was beginning to feel like the Terminator.

[Evil Roy Slade]

@wattsup
You won't like my answer but here it is anyway.

The thread you linked to is: Re: Self Running Micro TPU, with closed loop.

This implies the design goal of the circuit is to run without a power source forever.

Fundamentally this cannot happen. Hence an analysis of the circuit is irrelevant because
it is fundamentally flawed, no matter what combination of bits are put together.

If you choose to use the laws of physics to help design your circuits (e.g Ohm's law) then you
must accept them as being correct. Not some, but ALL of them. Ignoring the Laws won't make them go away.

Keep asking questions, think, learn. 

ERS

[EMdevices]

Guys,

I explained already how it works, and if you know basic electronics you will understand.   You can use Ohms law and other laws just fine. The device is super efficient because it recycle it's energy, but the charge in the main capacitor will run down eventualy due to the ever present LOSSES (resistance of the wires etc..) IT IS NOT OVER UNITY !!!!!

wattsup,   the transistor turns on when the voltage at the small cap connected to the base reaches about 0.6 V , or whatever the threshold is for your particular transistor.     The resistor R and capacitor C determine the PERIOD between flickers.    The larger the resistor value "R" and the larger the capacitance value "C" the longer the time between flickers of the LED.   I used big values like 1 M ohm and C = 22 u F , I even got it to flicker once every 15 seconds !!!  and the slower this flickering period, the longer it lasts, since the losses occur when it flickers occur, so less flikers per second less losses per second, so longer running time.   Other improvements can be made as well, and others are trying to squize it to perfection   LOL   

EM

[Evil Roy Slade]

@EM,

Thank you for the clarification. I did not read the whole thread and I apologise for
drawing an incorrect conclusion of the thread title.

ERS