The DC output of the opamp has a max output of 1.2V to 7.8V when its supply is 9.0V. The output DC voltage is 4.5V without a signal.
If the opamp's output is capacitor coupled to an ordinary diode that feeds a filter capacitor and a load resistor to ground then the max output to the encoder is only +2.65V.
But since the encoder needs an input of 5V then a DC amplifier must be used. A TL072 dual opamp can be used and its second opamp can be a DC amplifier. Its input must not be less than about +3V so level shifting must be used.
If the opamp's output is capacitor coupled to an ordinary diode that feeds a filter capacitor and a load resistor to ground then the max output to the encoder is only +2.65V.
But since the encoder needs an input of 5V then a DC amplifier must be used. A TL072 dual opamp can be used and its second opamp can be a DC amplifier. Its input must not be less than about +3V so level shifting must be used.