Hello everyone.

From the image.
How to trig SCR by TL494.
http://www.datasheetcatalog.org/datasheet/texasinstruments/tl494.pdf


please help.

 

That might not work at all well. The '494 is designed to do PWM. SCR's need phase control circuits to determine the percentage of voltage wave to pass. Try this IC - http://www.datasheetcatalog.com/datasheets_pdf/T/C/A/7/TCA785.shtml as an example.

 

thank you.