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Solid State Sleuths (Episode One)

Started by saturated, Today at 07:29:42 PM

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saturated

The case of "it looks like a transistor but might be a voltage regulator"  :grr

Some preliminary test results

Spoiler alert: I have no idea what it is

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At this point I think some resistance testing might tell us something

And I wish I remembered reading something about the base collector junction being reverse biased  xP

Maybe I can assume just arbitrarily designate one terminal as the base and go from there
Here in 1994
Things are different than before

saturated

Resistance results

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At this point I'm inclined to call terminal one the base
Terminal two the emitter
Terminal three the collector

Time to go look at some books 📚
Here in 1994
Things are different than before

saturated

Oh well figured I'd try it out

Made up a circuit gonna see if I can apply voltage until there is some emitter current

Was gonna have two power supplies but for now V1 = V2

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 xP
Here in 1994
Things are different than before

saturated

Change in plan

I put an LED between ground and emitter resistor

Looks like it works

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Now...idk why a clear white LED turns red when illuminated  xP

Ok to get a barely detected illuminated LED I have to have 1.7 V at the base and I get 4.2 mv across R3

Yeah I know it's a crap randomly assembled circuit
Here in 1994
Things are different than before

saturated

I think I might be out of luck yet .

No matter what I do the collector current is about twice the emitter current (voltage drops that is the resistors are the same value)

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At first i suspected the LED but the components are in series so the current and voltage drop should be the same

Might be time to ground the "emitter and see if it behaves like a voltage regulator  :grr
Here in 1994
Things are different than before

saturated

Alright guys the results are in but I'll wait  :tu:
Here in 1994
Things are different than before