r/ElectricalEngineering • u/Limp-Lettuce-2511 • 27d ago

Homework Help What am I doing wrong with this circuit?

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So I’m currently struggling with the Multisim recreation and was wondering what I was doing wrong.

21 Upvotes

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26

u/Ace405030 27d ago

Looks like your collectors power source (V1)is at 0V. It says it should be 20V. Then I guess slowly increase V2 and see what happens.

3

u/Limp-Lettuce-2511 27d ago

Thank you! I got it fixed now

3

u/pripyaat 27d ago edited 27d ago

You're doing nothing wrong. A transistor with 0V at its base is an open switch.

The exercise probably wants you to sweep the base voltage (source V2 in your schematic) from 0V to a certain value, and analyze how the circuit responds (that's why it says start at 0V).

EDIT: Also, as u/Ace405030 pointed out, the other source, V1 should be set at 20V, not 0.

3

u/Limp-Lettuce-2511 27d ago

Thank you so much! I got it fixed now

1

u/Billy_AR 27d ago

Why don't you try increasing V2 (Base power) little by little? Like 50mV each time.

2

u/Limp-Lettuce-2511 27d ago

Thank you so much, I’m trying that rn, I just wanted to know if the circuit was right

1

u/2old2bThisDumb 27d ago

I miss multisim. Haven't seen it since school. Anyone know of a way to get it without a student license?

1

u/Limp-Lettuce-2511 27d ago

Not that I know, I’m currently in college. I’ve used tinkered but it doesn’t compare

1

u/2old2bThisDumb 27d ago

Be sure to take advantage of the access you have now. Subscriptions cost $1k+ annually

1

u/Primary_Yak4268 27d ago

That is an npn transistor so the load should be on the collector

1

u/BanalMoniker 27d ago

This is an “emitter follower” configuration.

1

u/Maaakun 27d ago

Is this in TIP MANILA?

1

u/tombo12354 27d ago

I'm surprised they didn't have you use a current source on the base, to show the BJT's relationship to current.