Zero Crossing Detector

[NogginBoink]

I am designing my own circuit for lights control. I'm basing my zero-crossing detector on an article by Jeff Bachiochi in issue #193 of Circuit Cellar magazine. I'm using this design because I trust the magazine and the author and know that the author got it to work.

An excerpt from the magazine's schematic is below.

The author was using 5V parts, and my design is a 3.3V design. My question is: what values should I use for R9, R10, and R11?

I can do digital electronics all day long, but analog throws me for a loop.

Thanks for any input!

-Matt

[P. Short]

The values are not critical, use the ones provided. I suspect that he chose them because he had the parts on hand and they were the right order of magnitude, rather than doing any calculations.

--

Phil

[wjohn]

Analog is king, ya young whipper snapper, dog gone it!!!

(shuffles back to the couch, mattering about Valves were real digital ccts)

[NogginBoink]

This circuit appears to be causing me problems. Please see my posts in the thread at http://www.doityourselfchristmas.com/forum/viewtopic.php?p=9195#9195.