please help newbie clip LED passive

[I_Forgot]

You can use a second comparator to look for clipping on the negative side. Use a diodes to "or" the two comparator outputs to drive the 555 trigger input.

I_F

 

[DavidWardlaw]

wouldn't thost 1/4 watt resistors blow when massive current is passing through?

Also, wouldn't a special diode be needed as the one in your picture is used for DC, not AC?

 

[I_Forgot]

wouldn't thost 1/4 watt resistors blow when massive current is passing through?

Also, wouldn't a special diode be needed as the one in your picture is used for DC, not AC?

Which picture, which resistors, and which diodes are you referring to?
Current through a resistor depends on the applied voltage and the resistance (refer to Ohm's law). Power dissipated by a resistor is voltage^2/R. You can apply 1 million volts to a 1/4 watt resistor if the resistance is high enough (and the resistor is long enough ).

Diodes work for DC and AC.

I_F