# circuit help

Discussion in 'Homework Help' started by AC/DC kid, May 21, 2013.

1. ### AC/DC kid Thread Starter New Member

May 21, 2013
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Is this Low pass, High pass, Band pass, or Bandstop?

2. ### MrChips Moderator

Oct 2, 2009
12,446
3,361
None of the above. You have not indicated where is the output of the circuit.

3. ### Jony130 AAC Fanatic!

Feb 17, 2009
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Where is the output terminal? Or load resistance? And what is your guess?

4. ### AC/DC kid Thread Starter New Member

May 21, 2013
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I was thinking it was a Parallel resonant band-pass filter, but thats where i got confused seeing as it doesnt have an output. guess it is a trick question.

5. ### Veracohr Well-Known Member

Jan 3, 2011
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If it's a homework question I suggest you not dismiss it as a trick question. I've missed points due to NOT making assumptions.

6. ### AC/DC kid Thread Starter New Member

May 21, 2013
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It's a bonus part of a question, so that's also why i believe it to be a trick question as well.

7. ### AC/DC kid Thread Starter New Member

May 21, 2013
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Actually now i see i was wrong in saying it's a resonant band-pass filter. there is a low pass RC and a low pass RL filter in this circuit. so if we assume that R5 is the load then wouldn't it be a Band pass filter?

8. ### Jony130 AAC Fanatic!

Feb 17, 2009
3,957
1,097
Low pass filter + low pass filter = Band pass filter ? No, for sure.

First assume for "low frequancy" that C1 is a open circuit and L1 is a short circuit"
Next for "high frequancy" C1 is a short circuit and L1 is a open circuit.
So what type of a filter we have if R5 = LOAD resistance ?

9. ### bountyhunter Well-Known Member

Sep 7, 2009
2,498
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The first part (left hand) is resistors so it can be solved as a simple divider. To the right, you basically have a cap in parallel with an inductor. You should be able to figure what that does as frequency increases.

This looks similar to a crossover network for a speaker.

10. ### Ron H AAC Fanatic!

Apr 14, 2005
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What is meaning of that resistor that is scribbled in series with the capacitor?