Hello again,
Oh yes very good idea. It appears that the 150k ohm resistor may just be too high of a value for this circuit in that it allows too much line frequency noise pickup.
I'll run your circuit next...
LATER:
Ok, circuit doesnt run too bad i guess, but if you inject an AC source signal into the inverting terminal through a 1Megohm resistor you'll see the same effect as your video shows. It's harder to see in the analysis screen though, you have to look at 50ms or more, and you see the variation as an amplitude variation. Lowering the 150k to say 100k would help, going even lower would help even more.
Also, the NPN transistor allows a glitch to get through the circuit from the pulse source, a PNP shouldnt allow that either, but this may or may not bother you too much.