05-06-2015, 08:04 PM
I hate 555s, always have, but ....
This is a guess because I haven't tried to analyse it. Where I used to work we used a similar Circuit to generate what was called an 'Alarm Signal'. IC1 generates a low frequency which modulates the frequency of IC2 generating a 'Whoop, whoop' sound. IC1 discharges the C via the Diode but doesn't charge it up again. Unfortunately I can't get at the old Circuit any more.
Does IC2 oscillate ob its own?
Alan
This is a guess because I haven't tried to analyse it. Where I used to work we used a similar Circuit to generate what was called an 'Alarm Signal'. IC1 generates a low frequency which modulates the frequency of IC2 generating a 'Whoop, whoop' sound. IC1 discharges the C via the Diode but doesn't charge it up again. Unfortunately I can't get at the old Circuit any more.
Does IC2 oscillate ob its own?
Alan
