I'm working on building a square wave generator from a 555 and since I need higher voltage and current (negative polarity) to drive some power triodes, I have a PNP transistor between the 555 and the triode grid.
I think I hooked it up right, however I'm fairly new to transistor design so I may have done something obviously wrong. I'm wondering if the atypical polarity that I'm running the 555 at is an issue and how to get around this since a PNP needs a negative drive signal.
When I put a scope at test point B with ground reference, I get no signal, however if I cut the circuit at either cut A, C, or both, then I get a clean -12V square wave.
I imagine there is a better way to drive this transistor, any ideas to improve the circuit so it works?
I think I hooked it up right, however I'm fairly new to transistor design so I may have done something obviously wrong. I'm wondering if the atypical polarity that I'm running the 555 at is an issue and how to get around this since a PNP needs a negative drive signal.
When I put a scope at test point B with ground reference, I get no signal, however if I cut the circuit at either cut A, C, or both, then I get a clean -12V square wave.
I imagine there is a better way to drive this transistor, any ideas to improve the circuit so it works?
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