Servo2 is the possibility, to control two Servos without digital knick-knacks.
For more details please refer to the manual wDSA Handbuch 8.pdf, written by W.Hückel.
The software ServoAnsteuerung can be used to change parameters in hex-file.
The PCB fits into 'Merscheider Schacht', corresponding informations can be found here: https://kruemelsoft.hier-im-netz.de/schacht.htm.