PRO-2022 / PRO-2032
The Realistic PRO-2022 and PRO-2032 are almost identical. There is ample space to modify it with a discriminator output. The FM detector is an MC3361. The baseband audio can be found on pin 9 and TP5.
Pin 9 and TP5 contain the unfiltered audio
The connection to TP5: resistor and capacitor
Follow the next steps to make the discriminator output:
Overview of the discriminator output