help with these circuit pls...


Joined Jul 17, 2007
I'm not familiar with your "Circuit Wizard" software.

Sometimes macromodels (the PSpice netlist) for the 555 timers don't work exactly as they should; you can wind up with unexpected "glitches".

You're not showing the mandatory 0.1uF and >=1uF bypass caps across the 555 power pins; that's OK in a simulation, but just know that you have to use them on the real circuit.

As far as adding an opamp - I don't see how you'd add any functionality with it; and a 741 requires at least 9v across it's supply pins to see any output at all; it normally operates with ±15v supplies.