Hi guys,
For education purposes I'm attempting to chain together 2 CE amplifiers with an emitter follower between, but as you can see from the screenshot below, the waveform is obviously undesirable! The output from the first one was good, with a voltage gain of about 300, but this second stage is all wacky, with emitter DC voltage higher than the base voltage.
I added the emitter follower because, as I understand it, the Zin of the following stage should be about 10x the Zout of the previous stage, and 2 CE amps with a coupling cap wasn't giving me that ratio.
What's going on here? How can I chain these together, with the aim to increase gain, successfully?
EDIT: Couldn't seem to embed imgur image, so schematic is in attachment!
EDIT II: There is no load hidden behind the osc window, its just the osc leads going to the Q2's collector
For education purposes I'm attempting to chain together 2 CE amplifiers with an emitter follower between, but as you can see from the screenshot below, the waveform is obviously undesirable! The output from the first one was good, with a voltage gain of about 300, but this second stage is all wacky, with emitter DC voltage higher than the base voltage.
I added the emitter follower because, as I understand it, the Zin of the following stage should be about 10x the Zout of the previous stage, and 2 CE amps with a coupling cap wasn't giving me that ratio.
What's going on here? How can I chain these together, with the aim to increase gain, successfully?
EDIT: Couldn't seem to embed imgur image, so schematic is in attachment!
EDIT II: There is no load hidden behind the osc window, its just the osc leads going to the Q2's collector
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