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Transistor claims? is it real or is it "snake oil"?
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--- Quote from: mw2000 on June 29, 2019, 11:54:12 pm ---The guy that thinks they are snake oil said that both transistors are going to be subject to the same rules.

He told me that they will dissipate about 30 watts of heat if there is a 5 amp load on it.
His values were 14 volts in, 8 volts out, and 5 amps for the 30 watts of heat.
He did say this was an example of how to get an idea how much heat the transistor will produce.

Does that make the equation ( 14 - 8 ) * 5?

P = V * I? is that correct?


--- End quote ---

Yes.  The amount of power something dissipates (as heat, but in Watts) is exactly that P = V*I where V is the voltage *across* the device (in this case the Collector - emitter) and I is the current *through* it.  As it is being used as a regulator, any device with similar specs will work in its place, and all with have roughly the same dissipation - because the regulated voltage isn't going to change, and nor is the current consumption (current through the device).    That is how linear regulators work - they "drop" a voltage across them, and keep the output fixed when the input varies.  They get rid of this excess energy as heat.

So whilst others have said pretty much exactly the same thing, "the guy that thinks they snake oil" is correct.  No magic or special transistor will dissipate less power because that is precisely what the part is designed to do in this circuit.  Also as others have mentioned - I'm just laying it on thick here - the transistor packaging, and how it is mounted determines how hot it will get dissipating this power.
schmitt trigger:
Someone show this guy the basics of video editing, please!

The pair of linked Youtube videos could have been shortened by 90%, and no information would be missing.
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