[sdiy] differential subtractor vs summer with an inverted input

[Neil Johnson]

Hi,

David G. Dixon wrote:
> In other words, given E1 and E2, I want:
>
> EO = G(E1 - E2/4)

A differential amp with an attenuator/pad on the E2 input?  One op- 
amp, handful of resistors.

Neil
--
http://www.njohnson.co.uk