Connecting? Anybody knows how the 5pin din conector to the probe is wi

Need to find out how the 5 pin din conector is wired on a Siemens sonostat 733 ultrasonic device. To wire my own probe. Got a working device and i want to get a smaller probe (from China) that have a 2pin RCA to work with it. Its a old device and probes are hard to find it use to have other smaller probes as extra options.