I'm having a trouble selecting the proper transistor to switch this LED circuit
The LEDs are 3.6v at 20 mA.
I tried figuring the calculation for the transistor and really the maths escaped me so I just tried out a BC547 I had around. What really confused me was when the switch was open, the LED's glowed dimly. (When closed they glowed bright as expected). I was surprised as from what I'd read transistors are either full on or off. The dim glow was effected by me touching the resistor or other spots on the bread board.
If it helps, I'm actually testing this with the aim to replace the switch was a capacitive touch sensor such as this one: http://www.mouser.com/ds/2/42/iqs904_datasheet-8785.pdf
Finally I'm aiming to build this in SMD even though I'm prototyping in through-hole parts at the moment.
Any advice would be greatly appreciated.