Electronic dimmer circuit

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Zordon

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Hi, guys

I am building the following dimmer circuit however i am having alot of issues.
I built everything up to the optocoupler the 555 and zero crossing detector work great along with the npn transistor. I had the remove the coupling capacitor 0.001uF between zero crossing and 555 to get it to work.

https://www.onsemi.com/pub_link/Collateral/AND8011-D.PDF

The issues I am having are when trying to trigger the MOC3022. currently have an LED at the output however even without input output of MOC3022 is constantly shorted. When I attach my npn transistor with a pulsed waveform saturating at my top rail of 12V the voltage at the input of the MOC3022 drops to about 1.8V PWM.

Thanks in advance
 
currently have an LED at the output
you have the LED at the output of what?

output of MOC3022 is constantly shorted
How do you know that?

voltage at the input of the MOC3022 drops to about 1.8V PWM.

1.8 volts is the farward voltage drop of the LED inside the MOC3022 so that sounds right.
 
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