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Old 12-11-2016, 10:31 AM
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Quote:
Originally Posted by vts1134 View Post
Can anyone verify that the circuit I posted should work? I can't get anything out of it.
The problem is that the base is biased at about 1/2 of B+, which makes the emitter that (6 v) minus 0.7 volts = 5.3 v, and the collector drops to 12-5.3 = 6.7 v, so the transistor is almost saturated at one end of the circuit's output range. You need to reduce the lower base resistor or increase the top one to get about 3.7 volts at the base. Then the emitter will be at 3 volts and be able to swing almost from ground to 6 volts, while the collector will be at 9 volts and be able to swing almost from 6 to 12 volts.

You could try leaving the lower base resistor as 4.7k and increasing the upper one to 15k or 18k.
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