# Problem making a signal mixer

Discussion in 'Homework Help' started by jimgeor, Oct 29, 2013.

1. ### jimgeor Thread Starter New Member

Oct 29, 2013
1
0
So I was asked to make a signal mixer (using resistors only) that combines the signals V1, V2 where
V1 is a 1 kHz square wave that varies between 0V and +1V, and
V2 is a 5 kHz sine wave that varies between -1V and +1V
and produce a singal Vout where
Vout= (1/2)*V1 + (1/6)*V2

First of all I have a question
Does it matter what kind of source do we have?
I mean if we had for example a dc source or a square wave with different frequency would we do something different to solve the problem?

I started thinking that my circuit would be something like this
http://i1152.photobucket.com/albums/p495/jimgeor/my_circuit_zpsb14c0033.jpg
and then using the superposition theorem I would get two equations Vout=...*V1 and Vout=...*V2 where ... is two functions of R1 and R2
then I would take the first one equal to 1/2 and the second equal to 1/6
and then I would have a system of two equations
BUT my system has no solutions...
what am I doing wrong?
Can you give me a tip on how I should get start?