Quantcast
Channel: Active questions tagged feedback - Electrical Engineering Stack Exchange
Viewing all articles
Browse latest Browse all 227

How to calculate the current and voltages of this Sziklai pair?

$
0
0

This is a mic preamp with adjustable gain by potentiometer VR1

Im new to Sziklai pairs and could not find any information on how to do calculations for this case. Im trying to do DC calculations and the info i have : +IN and -IN are for AC source, the +VE and -VE are 15V. I want to know the currents of both pnp and npn transistors emitters, bases and collectors but since I need the base currents known (which i dont) to calculate the collector currents, I'm stuck.

Additional question:Are the resistors R3 and R4 meant as a voltage divider to make sure the voltage difference between emitter and base of Q2 is 0.7V? Or is R3 a feedback for the Sziklai pair in which case I'm not sure what R4 is for?

The original souce : https://www.sound-au.com/project66.htm

I would appreciate any help with the calculations and explanations.


Viewing all articles
Browse latest Browse all 227

Trending Articles



<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>