I am slowly learning about transistors. In my head I thought I had the theory of an NPN - a small voltage ~ 0.7V via the base can "switch on" the connection between the collector and emitter. I am not sure I have this correct though?
I have a simple cicuit setup as attached. When there is light on the LDR the LED stays off. When the LDR is covered, the LED comes on. However, it appears that the full current isn't being passed from the collector to the emitter, as I expected. That is, the LED is lighting up, but not to full strength.
Can someone help me out? Once the base is activated, shouldn't the full current flow from the C --> E ? The LED takes 100mA @ 12v so the N3904 should be able for that. What I am seeing is a dimmer LED that it should be
I have a simple cicuit setup as attached. When there is light on the LDR the LED stays off. When the LDR is covered, the LED comes on. However, it appears that the full current isn't being passed from the collector to the emitter, as I expected. That is, the LED is lighting up, but not to full strength.
Can someone help me out? Once the base is activated, shouldn't the full current flow from the C --> E ? The LED takes 100mA @ 12v so the N3904 should be able for that. What I am seeing is a dimmer LED that it should be
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