#### Electronman

##### New Member

Hi,

Today after getting several advices from audioguru I went to make a flasher based upon "cut off" and "saturation" regions of BJT transistors (I think it does work based upon those regions though!)

1: I would like to know if my design (resistor values) is just correct??

2: I want to know how to calculate the values for both capacitors (I think I have a RC circuit, if so how to calculate the values for say 2 seconds of blinking??)

3: My simulator does not show any blinking for the LED's with these used values and both are lightened simultaneously!? What's the problem really??!

Hope you guys specially professors "audioguru" and "MrAl" help me out to learn to design these switching circuit (though I am a newbie but I know the formulas for RC time constant circuits and Cut off/Saturation situations of a BJT)

Today after getting several advices from audioguru I went to make a flasher based upon "cut off" and "saturation" regions of BJT transistors (I think it does work based upon those regions though!)

1: I would like to know if my design (resistor values) is just correct??

2: I want to know how to calculate the values for both capacitors (I think I have a RC circuit, if so how to calculate the values for say 2 seconds of blinking??)

3: My simulator does not show any blinking for the LED's with these used values and both are lightened simultaneously!? What's the problem really??!

Hope you guys specially professors "audioguru" and "MrAl" help me out to learn to design these switching circuit (though I am a newbie but I know the formulas for RC time constant circuits and Cut off/Saturation situations of a BJT)