555 Boolean complete?

I've made a good many things with the timer. One of them that I still do when needed, is to connect a CT (current transformer) to the threshold input and have a short pulse to the the trigger input to switch the timer on. The idea is that if inrush currents are detected from the CT, it'll pulse the threshold input and hold it and the output will of course turn off a device. We've also used that trick for a precise torque detector in equipment that needed to retreat from what it's doing as a limit of the process, many drives just don't offer the quick response over that.

Years ago we made an array of STOP-START latches on a card slot rack for low voltage logic and optional timers via a jumper setting, then came along PLC's!

I just used one the other day to construct a basic FL HV supply for the display of Kenwood radio that went out to lunch.. Got some parts from one of those incandescent replacement fl lamps (FET, tranny etc) and cobbled together the rest and stuck it on the back of the display PB board via a little mini board I etched out via toner transfer!

It works, that is all that matters :)

Jamie

I've had more fun hacking them for analogish stuff - class D audio, switching LED power supplies, and NTSC sync lock. I never could get an AM radio receiver built with one because the original 555 generated massive EMF at those frequencies.

The proof that a Turing machine could be implemented in Conways game of life as a result of Gospers glider gun was a lot harder...

Or not enough 555's.

Cheers, James Arthur

Ya think?

Actually the one that busted my chops was the guy who implemented a fully working digital clock using *only* neon light bulbs for both the display and the logic!

Those small Ne2 were they called in orange?

It's on the web and iirc the only non-actives are tiny high value resistors and the Plexiglas case he built it in to show off his work.