Opto control for triac (CB20552E)

Found a documentation for PC from 1992, this circuit is indicated for the English power grid of 240 V.

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Cary, IL, USA — Coilcraft has introduced its new 0201HL Series of chip inductors available in...
Schmitt Trigger (MSB020E)
Schmitt Triggers convert a signal of any waveshape in square signals or pulses. The circuit shown...
Long delay using PUT (CB5151E)
This circuit was found in an American 1980s documentation. PUTs are rare today. Capacitors C1 and C2 are...