I am a beginner at electronics and I want to build a simple logic probe for TTL circuits. I found this diagram online:
Which does exactly what I want. However, I would like to make it play a high pitched sound when it is in high state and a low pitched sound when it detects a low state. I guess I would need some kind of speaker, but I don't know much about them, so basically I don't know where to begin or how to accomplish this, so any help will be appreciated.