>BTW, does anyone have schema of opto-isolated RS232 driver without
>external power supply? I need to communicate via RS232 with device
>that is on +48V potential (In tel. exchange as you can guess).

Why not use the ultimate opto-isolotion - Fiber Optic?  It's getting really
cheap these days.

Andy


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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
          Hardware & Software for Industry & R/C Hobbies
        "Go fast, turn right, and keep the wet side down!"
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