I am trying to make up a fridge door alarm, using 555 timer chips, but the 555 that provides the alarm tone from the buzzer, is just remaining high. I am still at the breadboard stage, and have just set up the astable circuit to get that working first, but it doesn't the output just stays high. The circuit is identical as the circuit here, except that the output is driving a piezo buzzer. I tried another 555 timer chip, same deal, are they both dead?