skmdmasud
Member
Hello..
i am a new member and very new to circuits. I built a timer based on CD4060 following this design 24Hr Timer {2} **broken link removed** **broken link removed**
as you can see there is a transistor BC557 which is a PNP type. What I dont understand is when there is no voltage in the Base of the tranaistor it keep on passing the +ve through emitter to collector and when there is voltage in base it stops switching??why?
As we know that transistors without any V in Base is like totally off.
Regards.
i am a new member and very new to circuits. I built a timer based on CD4060 following this design 24Hr Timer {2} **broken link removed** **broken link removed**
as you can see there is a transistor BC557 which is a PNP type. What I dont understand is when there is no voltage in the Base of the tranaistor it keep on passing the +ve through emitter to collector and when there is voltage in base it stops switching??why?
As we know that transistors without any V in Base is like totally off.
Regards.