I'm trying to find someone who is able to make a digital countdown timer? All it needs to do is be able to set a time preferable in minutes and/or seconds and countdown but the key bit is that once it hits zero it sounds a buzzer that doesn't stop until you push a button again. All the ones on the market here and on Aliexpress etc all stop at 30 or 60 seconds. Preferably AA or 9V powered etc.
So can anyone point me in the right direction? I'm even happy to have a crack at putting one together if there is a kit but it would be awesome if someone knew someone who could do it. Ultimately I'd need a few made and happy to pay accordingly.