I too have been toying with a couple of old Philips VCM8000 series cameras for some time now and already took Birdman Adams advice and peeked inside to have some idea what Philips/(Bosch, Magnavox) is doing with their proprietary 4-wire connection but have had no luck finding definite signal pin-out information on the Web to date. These are rugged little cameras and with .5 lux at 380 lines performance is a shame to toss them in the trash.
I think the first thing we need to do is forget about wire colors. These cameras use 6-pin RJ-11 connector with a UTP on pins 2-3 and another UTP on pins 4-5 to send power to the camera and return video, audio, and a dry contact alarm signal to the switcher; pretty slick trick. It appears they'll work on 9.6-27 VDC with nominal 45VDC.
kujina - can you confirm the Monitor/Switcher is putting +45V on pin 3 and common on Pin 2? Looking at artwork and capacitor/diode polarities on the PWB it appears to me my VCM8000 series camera is powered by via pins 4 (+) and 5 (-).
Pins 2-3 are driven by a balanced circuit on the camera internal PWB. There's a 4 terminal device on the PWB which appears to be an isolator between the RJ-11 connector and camera internals. In the non-alarm camera there's nothing else between this 4-terminal device and pins 2 and 3 of the RJ-11 connector. This device could be a transformer or, more likely, an optical isolator. I found no continuity between the RJ-11 and camera sides of this 4 terminal device. Audio is injected to both pins on camera side of the 4 terminal device through a 4.7uF Cap and a resistor divider.
I read on another Forum someone believes video is carried on the + power line. There might be some truth to this as there are some pretty large chokes on both the + and - traces inside these cameras.
Everyone sure there isn't someone out there with an old service manual for the system monitor/switcher with schematic? I'd love to hear about it!
v/r
Bob