Hey guys. So I do DT Systems and Control GCSE level, and I'm completely stuck on my coursework. I've been trying to get my circuit right and working the past few days but I just can't identify the problem. I go to a boarding school and our holidays start in two days, therefore, my due date is basically in two days. So onto the problem. My circuit is a monostable 555 timer which is connected to a transistor switching circuit. What happens is there is a pressure pad which someone steps on, and the circuit is meant to turn a motor to turn a platform. At first, the motor didn't even turn on, and I had absolutely no idea why. So I just desoldered various components like the capacitor - which I replaced with another one - as well as the diode which I replaced with an LED. That was a bad idea as it seemed the transistor and the LED was overheating as a result, but I did find out that when I touched the collector and base (of the BC108) together, the LED turned on and the motor turned! So I resoldered the diode back in and thought about doing something I know is absolutely crazy, but I was just so desperate. I put a little bit of solder between the collector and base so they were connected, and the motor turned! Now, this led to other massive problems. First of all, the circuit now does not even switch off, and secondly, the circuit doesn't turn on only when I step on the pressure pad, it turns on immediately after I connect the battery. So, someone please help me as I am so stuck and only have pretty much two days left. Oh god....
PS: My circuit is a PCB with copper
PS: My circuit is a PCB with copper
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