Salvaging electronics do not only work for supplying your hobby with cheap parts, also cheap laugh 🙂
Here is a on/off switch from a 1980’s transistor radio, having a capacitor across the AC terminals is not strange and will protect the circuit in some degree from surges on the power distribution network.
But naming such capacitor a Spark Killer on the PCB is something new to see for me
Have a nice weekend, I certainly have one 🙂
That is certainly an interesting find you have there! Maybe it is an inside joke between the circuit/PCB design team?