I need a inexpensive (i.e. not packaged) solution to delivering clean Power over Ethernet at gigabit rates. Yes, I know that balun imbalance will limit how clean it can be - but I'd still rather not bring unnecessary noise into the remote (box (a radio).
I don't want to buy a commercial packaged solution for injecting power, because most don't care at all about noise (I've measured *volts* at hundreds of KHz), and they're expensive.
So I'd like to find a passive gigabit Ethernet isolator - a pair of RJ45 sockets with magnetics, so I can inject my own power from a cleaner supply. I've come up with nothing in my searches. Can anyone help?
At the powered end, a normal Gbit Ethernet socket (with magnetics) is acceptable - but they're still over $10 or so at stockists. Clearly those who manufacture routers don't pay those silly prices, so there must be a cheaper source. Any thoughts?
I could use external magnetics following a simple socket, but I would still have to route the Gbit traces, so an integrated socket is preferred.
Finally, 4PPoE is allowed to deliver 57V, with the expectation that after 100m drop across the 4 pairs, it will be 48V. Those voltages are inconveniently high for most switch-mode voltage droppers. What you use to drop this to, say, 12V at 3 or 4A?
Clifford Heath.