Hi all,

Many years ago I designed a little remote indicator circuit. Nothing
too fancy. It communicates over RS485 at 250kbps. Similar to DMX, but
not quite the same.

I've recently had the idea to make a few new ones, but remotely
powered. I'd like to try to vaguely follow the power over Ethernet
(PoE) ideas as I think it would be an interesting design challenge.
The basic idea is to apply a common mode voltage to the differential
pairs.

The power side is fine, I can work that out. What I don't know is if I
can use an Ethernet pulse transformer for a different signal. On the
surface, it seems plausible as both are differential signals. But I
would guess my speeds are significantly lower, and I have no
experience designing anything like this.

Am I totally out to lunch, or might this actually be possible?

Josh
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