[sdiy] A little OT, Begging a hand

[Ian Fritz]

At 04:30 PM 2/8/2011, Ian Fritz wrote:

>>The problem is soluble.  We know that G8 = 1/2k2, and we have six equations
>>for six conductances:
>>
>>G1 - G6 = 0
>>
>>G1*(VA - V1) + G2*(VA - VB) + G4*(VA - VC) = 0
>>
>>G2*(VB - VA) + G3*(VB - V2) + G57*(VB - VC) = 0
>>
>>G6*(Vout - VC) + G8*(Vout - V3) = 0
>>
>>G57*(VC - VB) + G4*(VC - VA) + G6*(VC - Vout) = 0
>>
>>1/G1 + 1/G2 + 1/G3 = 1/K
>>
>>This will give us G1, G2, G3, G4, G57, G6 and G8.

You are forgetting that you have to also solve for V0, since it is a 
dependent variable (not an applied voltage).  So you have one more 
variables than equations.

You have, in fact, just proved that the system is not solvable.

Ian