Quote:
Originally Posted by old_tv_nut
1) Please tell me you are not using the circuit with the emitter tied directly to ground instead of through a resistor.
2)Are you using the collector output (which is inverted)? In that case, the gain is equal to the ratio of the collector resistor divided by the emitter resistor. Without the emitter resistor, the gain is very non-linear and depends on the amount of current in the transistor, which varies the effective emitter impedance. So, to get the gain you want, divide the collector resistor by the gain needed and use that value for the emitter resistor.
3) a fine point to add: if the following circuit (connected to the collector) has a high impedance (like a tube grid), all is well, but if it has a lower impedance, closer to the collector resistor, it will reduce the gain because it reduces the total effective resistance at the collector.
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OK, I remade the inverter following this schematic, with the exception of the 2.2 K resistor which is a potentiometer/parallel resistor of the same overall value. The output is greatly improved. One problem I am having is what looks to be vertical interference as you can see from this video. The vertical bars look like a horizontal problem in the television, but it's in the video itself. When I adjust the potentiometer you can see at some point the vertical bars change direction. Thoughts?
https://www.youtube.com/watch?v=G7Xc...&feature=share