How to invert an analog signal?

[ericgibbs]

They are 10K pots. There are two of them, one for gas and one for brake. I'm not worried about removing the first opamp; its no problem to build, and since its a dual opamp chip, its not like it requires too many extra parts

hi,
As the gamer pots are 10K, dropping the buffer would be OK, if you want to.
If you do decide to drop it, just connect the +/-inputs to 0v thru a low value resistor. I dont like to leave inputs floating.

IIRC its just the 'gas' pedal thats upside down.

Eric

EDIT:
To show that it works, a gif [using a CA3420 dual OPA]

 

[toodles]

Seeing that makes me very happy. Just to be safe, I'll go ahead and implement both halves.

What program or tool is that you used for the plotting?

 

[ericgibbs]

Seeing that makes me very happy. Just to be safe, I'll go ahead and implement both halves.

What program or tool is that you used for the plotting?

Hi,
For the PC plotting I use a MCP3202 dual 12 Bit ADC, connected to my parallel port. I have a requirement from time to time to plot the state of external projects.

So I designed and built the ADC unit, I write all my own software, in that way I can tweak it do the tests I need to run
Currently I am extending the features in the unit/program to cover another job.

Its not high speed, it runs at about 50 dual samples/sec, but its ideal for monitoring the state of psu's, battery chargers and OPA's.

On your system, set the Vref to +1.5V before you connect to your Gamer input, this will ensure that you dont apply more than +3V to the inputs.

Eric