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Apologies got busy last night, things fell apart.
Heres a schem I found, the diode keeps the op amp o/p a diode drop above ground so it always conducting, this circuit will only work reliably if the op amp i/p is kept above ground, some op amps dont like it if you try to drve the o/p below or above the rails, you could give this circuit gain by adding resistors.
Speaking of which in #7 I mentioned care is required in op amp selection, thats one of the reasons for the diodes in #8, they protect the op amp from the i/p going outside the rails.
There are if you look in suppliers blurb op amps that are meat for single rail supp;y such as the Lm358 (which would probably be fine wthout the diode below, you'd need that for something like the wonderful 741), its been with us a long time and is capable of simple applications.View attachment 125119
I thought the goal was an absolute value amplifier?
Your schematic is simply a half-wave rectifier that clips the peak of a 24v p-p input signal by one diode drop.