After seeing our Larson Scanner kit, Martin shared this LED metronome project with us. Martin says:
It was designed as a “Visual Metronome” So a learning music student could help see the timing by watching the green light. There was to be an optional clicking sound by using a small solenoid for the ticking – I chose that in place of a speaker for a more authentic sound.
The timing is a standard 555 timer which is fed to 7442 BCD to DECIMAL counter. Next chip is a 74193 UP/DOWN counter. When the count hits the last number, it sends a pulse to reverse the count or start over – depending on the toggle switch on the side.
There is also a pot on the 555 to control the speed. All this was made in one night while I was working the graveyard shift.
The entire LED display was hand wired using a manual wire-wrap tool.
The chip pin labels on the back of the perf board are a particularly awesome relic of a different era of electronics assembly. Thanks for sharing your project photos and video with us!