Chad

Try Communica  : rca to coaxial connectors - Communica South Africa

In the past we were supplied with specialized connectors by Hiconnex as well.  Maybe it's worth a try?

thanks. It's actually for a depth sounder transducer on a sailboat. Existing through-hull transducer (RCA) instrument is damaged beyond repair. Alternate display unit uses co-axial, but transducer is mounted inboard and thus less reliable. I want to connect the RCA cabled transducer to the co-axial device. Figured it was a bit complicated to explain the context in the original post 😉 

To be honest with you I am BC,  before computers. this custom-made program was developed by my son. All I know is that he used Modbus protocol to interrogate both the battery and the inverters and Narada for visual graphs. We use a Raspberry PI to interface with both inverters and battery.