Q:

555 trigger frequency signal

So, I'm remembering that back in school, I managed to make a 555 signal create a tone signal, and that another 555 could trigger the 555, such that I had a variable toned signal that could be pulsed. IE, I could change the frequency, and pulse the frequency. IE, I could have 3 pulse per second of a 1Kz tone. I've been trying to figure out how to do this circuit today, and have been having problems with one small portion of it. I can create the tone, create the pulses, but I can't seem to make the pulses trigger the higher frequency signal, I can't figure out how to trigger it. What am I missing?

A:

The usual way to do it is to connect the output of the low-frequency 555 to the reset input of the high-frequency 555, so that the latter is "gated" by the pulses of the former.

