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Old 4th Mar 2005, 10:59 am   #38
ppppenguin
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Default Re: Multi-Channel VHF Modulator Design

It really doesn't make much difference for an emitter follower (unlike a common emitter stage where the input and output are referenced to different power rails). A small amount of muck on the +ve rail can be injected via the bias chain for PNP or NPN. For NPN there is virtually no sensitivity to the +ve rail. For PNP it's a very slight sensitivity due to the finite output impedance.
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