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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TTL and CMOS Optical Shield (CB4248E)
This circuit, from an old ON Semiconductor publication, suggests a shield to excite an LED from an...
Auto Stabilized Zener using the 741 (CB1283E)
The FET of this circuit of a 1971 publication may be the BF245. The circuit serves as a voltage...