Serial ground isolated serial connector (Neptune)

[simonh]

Hi,

Does anyone know what components are inside the Ground Isolated Serial Connector and if they are easy to make?

I don't have a Neptune but a different computer. It too suffers from a slight change in the pH, Temperature readings when plugged into the computer serial port. Unfortunatley I can't find one of these isolation devices over in England and am wondering how easy it would be to make one.

[Doug]

Hi Simon,

I am not sure what is inside the part that they sell but I wonder if you could run a small guage wire from the jacket on the db9 or db25 connector on your computer to a cold water pipe? I am not sure if this would give you the same results but if you have some wire laying around maybe you could try it out.

Doug

[simonh]

I've done some more research and it seems there are quite a few devices around which do this. Basically it uses opto-isolator chips and is a little more complex to build one that I had hoped. Hopefully I can ring around a few local places tommorrow to get some prices.