I've had no luck searching Google for terms like RCA power connector, other than a passing reference on Wikipedia. I have plenty of RCA connectors, and tons of wall warts. I've got a small LED desk lamp that I want to power with a wall wart instead of a battery, but I don't have any female connectors that the wall warts plug into.
So my thought was to use an adapter and change the end to be an RCA connector. If I'm putting a few volts and maybe 500mA or so, would there be any problem as far as the RCA
connectors go? Obviously I'll need to reduce the voltage for the LED and I'll have to deal with those concerns, but if there's any problems with the connector I'll just try to find some standard connectors.
In my experience RCA plugs make a very tight connection, and I expect the resistance to be way less than 50 mΩ, probably near 10 mΩ. Even at 2 times 50 mΩ (you have to count both pin and sleeve) a 500 mA current will cause a 25 mW dissipation, which is more than acceptable.
Matt makes a valid point about mixing them up with audio plugs, though. The wall-wart probably has a DC jack like this
Why not use a socket for that? These are almost exclusively used for power supplies, so there's little chance of confusing them for something else. Sockets for them are readily available.