I'm pretty new to the hardware side of electronics and am building some basic logic gates. The first Im trying is an AND gate and the problem I'm having is that whenever I power the base of the transistor it's emitting power even with no power going through the collector. Any ideas as to why? Thanks. (Am using a BC475 transistor)
The base-emitter junction forms a diode. If the base voltage is higher than the emitter voltage by more than about ~0.6V, current will flow even if there's nothing attached to the collector.