# Small alarm system circuit analysis

• simphys
simphys
Thread moved from the technical forums to the schoolwork forums
TL;DR Summary: Hey, I was hoping for some help on how I would be able to calculate the minimum and maximum frequency that can reached with the potentiometer and also how this circuit works intuitively, because I don't really understand it. Thanks in advance!

Hey,
The TL;DR sums it up. I don't really get how I can determine the maximum and minimum frequencies that can be obtained. I vaguely understand how the circuit works, but not how to determine the frequencies.

Last edited:
Baluncore said:
Is this homework ?
What documentation have you been given ?
Do you know what is inside the LM555 package ?
https://en.wikipedia.org/wiki/555_timer_IC
Yes I am sorry, I should have said this earlier but I figured it out.. It is a lab report. I didn't read the documentation through for this one. This comes down to the arrangement of an astable operator basically.
I was trying to understand why the components were arranged that way, and how the capacitor was discharging at 2/3 Vcc but that happens internally :'D.

As to the frequencies, those can be calculated with the formula from the datahseet.

Baluncore
simphys said:
Yes I am sorry, I should have said this earlier but I figured it out.. It is a lab report.
Thread has been moved to the schoolwork forums now. Please take care to always post schoolwork questions in the Homework Help forums, and show lots of work. We do not do your schoolwork for you here at PF.

simphys said:
I didn't read the documentation through for this one.
Then do it. The datasheets for the 555 ICs generally have a long "Applications" section with lots of explanation about how they work. Please do that reading now, and come back here to this thread if you have specific questions.

• Engineering and Comp Sci Homework Help
Replies
13
Views
2K
• Engineering and Comp Sci Homework Help
Replies
4
Views
856
• Engineering and Comp Sci Homework Help
Replies
6
Views
2K
• Engineering and Comp Sci Homework Help
Replies
22
Views
2K
• Engineering and Comp Sci Homework Help
Replies
4
Views
908
• Engineering and Comp Sci Homework Help
Replies
10
Views
1K
• Engineering and Comp Sci Homework Help
Replies
3
Views
971
• Engineering and Comp Sci Homework Help
Replies
2
Views
1K
• Introductory Physics Homework Help
Replies
4
Views
506
• Engineering and Comp Sci Homework Help
Replies
1
Views
588