I'm making a piezo siren with motion pir sensor. I soldered the siren part and no noise so I guess I scrapped little flux off to get it working, that's really bizarre. It's very sensive. Lol. I put my finger barely on the contacts, it changes tone. I'm ready for soldering the rest of it for the motion part. I also love the 555 timer, but I'm not used to using it as much.
