A tuning fork (mounted on a resonance box) is made to resonate when a second identical tuning fork is rung nearby. This is beacause the first tuning fork's driving frequncy is the same as the second ...

Two identical tuning forks mounted on resonance boxes are struck with rubber mallets to show they have identical tones. A small piece of putty is added to one tuning fork to alter it's frequency. When ...

[Willem Koopman aka Secretbatcave] was looking at a master clock he has in his collection which was quite a noisy device, but wanted to use the matching solenoid slave clock mechanism he had to hand.