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suitable Collector voltage?

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Willen

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Replacing the transistor (if it fails) means changing the value of the resistor, usually to obtain a specific voltage - mostly on the collector of the transistor.

Asking same type of question- How to know that which voltage (2V or 3V or 4V or 5V?) is suitable for Collector voltage?
 
A good bias network fixes Ie at a specific value. Then Ic = alpha*Ie. Alpha is hfe/(hfe+1). Alpha varies a tiny amount, from about 0.980 to 0.998, while hfe varies maybe 50 to 500. As posters have stated above, negative feedback neutralizes variations due to hfe, temperature, gm, Ies, Ics, etc. Good bias network design results in an amp stage whose performance is consistent and predictable despite parameter variations for individual parts as well as temp and operating point.
 
A suitable collector voltage is largely determined by the output signal swing. It has to be sufficient to allow the full pp signal output without clipping.
 
Hm... hFE is current depended, then the first step of designing a biasing (amp circuit) is to determine that how much current flow will take place (I think). But how they will know that before making it!

Can you explation the steps of designing a simple amp circuit which has (with calculation if simple):
- 5V supply
- General transistor
- Base bias resistors (divider)
- Collector resistor
- Emitter resistor
- an electret Mic with its 10k bias resistor
- a coupling capacitor

other parameters create yourself please! I think designing such circuit has little chain of equations but don't know where is starting point!
 
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