- #1
likephysics
- 636
- 2
A bit confused about how it works.
Link - http://www.technologystudent.com/elec1/transis2.htm (3rd fig from top)
The way I understand, transistor TR1's Base-emitter conducts, which fwd biases B-E junction of TR2. This in turn will turn on the lamp, but it won't be really bright.
Once its on, the collector of TR1 is at +Vcc minus the drop across the lamp. This will increase emitter current of TR1, which in turn increases the base current going to TR2, which is amplified and makes the lamp glow even more.
Correct?
Also, why is TR1's collector connected to lamp instead of Vcc?
Link - http://www.technologystudent.com/elec1/transis2.htm (3rd fig from top)
The way I understand, transistor TR1's Base-emitter conducts, which fwd biases B-E junction of TR2. This in turn will turn on the lamp, but it won't be really bright.
Once its on, the collector of TR1 is at +Vcc minus the drop across the lamp. This will increase emitter current of TR1, which in turn increases the base current going to TR2, which is amplified and makes the lamp glow even more.
Correct?
Also, why is TR1's collector connected to lamp instead of Vcc?