PC Heat Alarm Circuit Help

[kateey27]

I've connected this circuit on a breadboard and repeated it 3 times just to make sure that I did it correctly. However, when I plug it into the host PC and I actively increase the temperature of my PC to a high one (around 90degC), it doesn't beep. I also tried changing the VR1's reference voltage a few times. I know that there's power flowing through for there's static-like sounds from the speaker. I just don't know what I'm doing wrong. Any ideas?

PLEASE HELP ME!!!

(Here's the link to the circuit I'm trying to build: http://www.ecircuitslab.com/2012/05/pc-temperature-alarm.html

 

[Hero999]

Wow what a complicated way of doing it. Rather than a CA3130, two 555s and a speaker, I'd opt for an LM393 and a piezo buzzer.

Have you tried testing the astable part of the circuit separately?