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December 01, 2025, 03:33:30 AM

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I just did some headbanging

Started by saturated, June 28, 2025, 01:12:21 AM

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saturated

So I was doing an experiment per textbook

Take a 2n3904 ground the base
Put +12 at the collector resistor
Put -12 at the emitter resistor

Ok that in itself was quite a task but I managed and no matter what kept getting a Ve of -3.7v

It took me a while to figure that if base was at ground then thats probably not correct.

So I reconnected configurations ad nauseum and kept getting the same thing  :grr

Meanwhile kept checking that VB = ground.

Finally I was like well hell why don't you check the transistor so I did a diode check with my multimeter and + on base to emitter was showing a one.   :loco

So I grabbed a new one and it showed about 0.67  xP

Ve with new one in circuit

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Ve with old one in circuit

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And the diagram

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Now the "old" transistor is pretty new from mouser a year or two ago but..to be fair is has been subjected to some abuse like reverse biasing and stuff....

Anyhow I thought I was going crazy  :'(


I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

saturated

Tested by the atlas

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 xP
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome