Hi there, complete beginner here, and my first time using transistors so apologies if this seems stupidly simple.
Basically i'm trying to use 2 arduino output pins through BC639 NPNs as switches to charge/discharge a capacitor from a 7.2v battery through an LED.
The issue i'm having is that on the breadboard the LED lights up after a few seconds of the top transistor being powered even when the second transistor is 'off' (base-emitter current from Arduino is zero) which I don't want. I believe it has something to do with capacitor voltage across the collector-emitter causing the second transistor to 'leak' but i'm not sure
I'm at a bit of a loss as to whats going on so if anyone could guide me in the right direction here that would be great.
heres the data sheet for the Transistors i'm using if it helps at all : http://www.rapidonline.com/pdf/81-0080.pdf