Hey Folks,
I have a question about the diode clipping in the Bazz Fuss...
Diagrams I have seen of diode clipping always have the diode(s) going to ground, with the signal travelling past getting diverted (correct way of looking at it?) once the diode's threshold voltage is exceeded. In the Bazz Fuss however you have the diode between the transistor's collector and base. In this case, what is happening here to create clipping?
Many thanks,
ff
Diode clipping in Bazz Fuss question
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juanro
- Cap Cooler
The diode is there to provide biasing, not clipping. A very unstable and non-linear biasing...
As long as collector voltage is higher than the diode threshold + Vbe, the diode and the BE junction of the transistor conduct, current flows (base current) and thus collector current flows and collector voltage drops.... until the equilibrium is reached, with around 1V of collector V. Then any small positive signal applied to the base (the guitar) will turn the transistor fully into saturation and vC will drop to near 0, and any negative signal will "rob" some diode current and let the collector go a litter higher to balance things, that's the clipping. Hard on the way down, and a bit softer when going up.
Regards,
Juanro
As long as collector voltage is higher than the diode threshold + Vbe, the diode and the BE junction of the transistor conduct, current flows (base current) and thus collector current flows and collector voltage drops.... until the equilibrium is reached, with around 1V of collector V. Then any small positive signal applied to the base (the guitar) will turn the transistor fully into saturation and vC will drop to near 0, and any negative signal will "rob" some diode current and let the collector go a litter higher to balance things, that's the clipping. Hard on the way down, and a bit softer when going up.
Regards,
Juanro
La única verdad es la realidad.