Here I try to describe how I found the way of communication between the antenna and the “databox”:
The cable of the antenna had 5 wires connected to its pcb. With the handyscope of TiePie I checked those contacts for data signals and found RS232 data. See last picture. With help of a Wemos D1 R2 pcb and the arduino IDE I managed to process the RFID data. The data was just the unique RFID-number.
(15p[new] instead of 9p[old])
