Hi. A couple of month ago I initiated a thread about doing o-scope measuring on mains connected equipment. The solutions was "isolation probes" or using an isolation transformer to power the scope. I checked both solutions and found both beeing a bit costly... Now, a couple of days ago Oliver Broad mentioned the ISO122 parts from "Burr-Brown Corporation Division of Texas Instruments" (phu, what a name !) in another thread (the "phone line" one). I'v checked these parts (and ordered a couple) and it seems as you should be able to built a probe-frontend with these. Looks good from the data sheet. Now, has anyone done anything with these ISO122's ? Any tip to share ? As how to supply the two +- power supplys ? An easy solution would be 4 9V batteries. Jan-Erik. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads