Quote:
Originally Posted by Argus25
Yes, as Craig Sawyers pointed out the fT is an important parameter for the application, but as you say a silicon transistor's fT is easily shifted downward by adding a small amount of base to collector capacitance to make it behave like a germanium in terms of its frequency response.
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Indeed. Fiddling around on Spice with a common emitter stage with an Ic of 1mA, a supply of 10V and a gain of 20dB, adding 33pF collector emitter reduces the 3dB point to around 800kHz regardless of the fT of the transistor.