Weird JVC 503B "RF converter" pinout?

[luRaichu]

Well, it's an RF modulator all right, and it works. The pinout is:

1 - Ground
2 - Audio
3 - Video
4 - RF output
5 - +12v
6 - Ground

For my use case I put -12v on ground. You must have 12v for optimal picture quality. Which also means you can run this module off a car's cigarette lighter but that's besides the point.
Too bad +12v accidentally came across my video source during experimentation and wrecked the Raspberry Pi's composite output. Luckily, HDMI can be used and this unit only costs $15. Still feels stupid though!