Originally Posted by ronv
I didn't see the exact article, but the 555 has a totem pole output that draws a lot of current when it switches. I suppose this is worse if say you are using a 9 volt battery with high internal resistance. Most of the datasheets recommend decoupling the supply close to the device.
Yes, he does get some strange ones.
I remember building an alarm circuit with a 555 which would cycle on and off when tripped. I breadboarded in my lab (bedroom) and was watching my little B+W TV which used a rabbit ear antenna:
Each time the 555 switched states, the picture on the TV would completely fuzz out. They can make some serious noise unless well decoupled.