Converting Bosch/Phillips VCM7C RJ11E Cameras to BNC - HELP!

[kujina 0]

Hello members I need to convert the RJ11 ends of four Bosch cameras (from a Bosch eazeo system) to work on a new DVR with BNC inputs.

 

The Specs of the Bosch VCM7D130/00T Cameras are:

 

Connection TP 4-pole RJ11E - 4-wire dual twisted pair (Video, Audio, Power, Comm.)

Input Voltage 24 VDC

Power Consumption < 2 W

 

I believe the wiring is as follows (the power and ground are definitely correct, I tested with multimeter)

http://www.instructables.com/files/deriv/FC5/C0CG/GA1BSSQ1/FC5C0CGGA1BSSQ1.LARGE.jpg

 

I made a converter (tried video on both remaining wires) but it didn't work, am I correct in thinking its because I need a to use a Balun?

 

I think this might Work!

If I chop off the RJ11 connectors on the DVR end of the camera cables and fit RJ45 connectors and then buy these it should work right?

 

[Soundy 1]

What is the cable at the bottom of the picture - is that connected to the RJ11, or just something there for illustration??

 

I wouldn't assume that black and red are power, or even that black is common - the color codes you show on the jack are standard layout for RJ11 phone connections. It would make sense that they would use those colors as such, but I wouldn't count on it.

 

Are you sure the cameras are actually working? Do they at least have a power LED that comes on when you power them up?

 

You shouldn't NEED baluns to get a signal. You might get a noisy/scrambled picture if the camera has an internal balun, but you should still see something.

[Birdman Adam 0]

My prediction on the wiring: I would think that red would be positive 12VDC, and black is ground. Yellow is almost always the video signal, and the video ground is again the black wire. The green wire is probably audio then, and once again the black is ground.

 

To really be sure of the wires I would open up the camera and see where the wires go.

 

For example, the red + black may go to a voltage regulator (then you will know those are the power wires). Or maybe the wires are labeled on the PCB. (They do that pretty often). Maybe you can see the yellow wire coming from the processor of the camera? Or maybe the green wire is coming off a circuit with a small microphone (will probably look like a button battery).

[kujina 0]

Thanks for the replys!

 

What is the cable at the bottom of the picture - is that connected to the RJ11, or just something there for illustration??

 

I wouldn't assume that black and red are power, or even that black is common - the color codes you show on the jack are standard layout for RJ11 phone connections. It would make sense that they would use those colors as such, but I wouldn't count on it

The wiring diagram picture isnt mine its from Instructables.com, I didnt actually notice the colours of the wires but rather the pin assignments, and the position for power and common/ground is the same as in the diagram

 

The cameras are definitely in working order because they are still connected to the original surveillance system

and I measured (using a multimeter) the voltage from an rj11 input jack on the back of that unit, therefore the pin assignments for Power & common/ground is know to me and the voltage of 24 Vdc is confirmed also.

 

You shouldn't NEED baluns to get a signal. You might get a noisy/scrambled picture if the camera has an internal balun, but you should still see something.

I didnt get any picture at all when trying my previous converter on the new Avtech DVR and I tried both remaining wires, one of which must be audio and must be video.

 

As far as baluns goes it does seem I need them (on DVR end) as I read a couple of threads on forums just before making this thread, one is here

 

Also on wiki in regards to Baluns, UTP cable and video it says "A balun is also used on the video recorder end to convert back from the 100-ohm balanced to 75-ohm unbalanced."

[Soundy 1]

The cameras are definitely in working order because they are still connected to the original surveillance system

and I measured (using a multimeter) the voltage from an rj11 input jack on the back of that unit, therefore the pin assignments for Power & common/ground is know to me and the voltage of 24 Vdc is confirmed also.

Got it. Good work confirming it

 

You shouldn't NEED baluns to get a signal. You might get a noisy/scrambled picture if the camera has an internal balun, but you should still see something.

I didnt get any picture at all when trying my previous converter on the new Avtech DVR and I tried both remaining wires, one of which must be audio and must be video.

 

As far as baluns goes it does seem I need them (on DVR end) as I read a couple of threads on forums just before making this post, one is here

 

Also on wiki in regards to Baluns, UTP cable and video it says "A balun is also used on the video recorder end to convert back from the 100-ohm balanced to 75-ohm unbalanced."

All it's doing, though, is level-matching and aiding noise rejection - you CAN actually use a balun on only one end of a line, you just won't get the full benefit of a pair of them.

 

The information in that other forum doesn't appear to be entirely accurate... "sph" has a bit of a clue what's going on but doesn't seem to have a complete grasp of how video works (eg. "The Balun just matches the electrical properties of different gauge/material wire" is nonsense). That said, I do stand to be corrected on such proprietary systems, since I've not had to deal with these particular ones, but IN THEORY, there's no reason a second balun should be required.

 

Nevertheless, his last suggestion is probably the best one overall: "Personally I'd forget the experimentation and get new cameras." Unless you're experimenting for the sake of experimenting, cheap $20 eBay cameras would probably work just as well as what you have, and would use standard BNC or RCA connections along with standard 12VDC power (24VDC is almost unheard-of in CCTV).

[Beev 0]

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

[sushizar 0]

hello

I don't understand very well.

 

This topic his exactly what i want.

 

But what is the response.

I'm test the first draw but no ok.

I have the same system of camera and multiplex, i want recupered the camera for anothe thing but i don't know the color .

 

i have the red, black, green, yelow.

 

power is 24Volt.

 

what is the real color of power +

what is the real color of power -

what is the real color of video

 

i try power 24v in red, video in green and the commun - black but i saw some spark .

 

one question

what color in what hole

 

merci à tous

gracias à todos

[Beev 0]

sushizar - You have to work with pin numbers, not colors. Most commercial RJ dongles will follow Telco Tip/Ring color scheme which is not the same convention as low voltage Audio/video. I'm still holding out for someone with the Monitor from this Phillips PnP CCTV system in order to learn what signal I/O is in one of the camera ports.

[jvc_master 0]

Hello,

 

i have the problem solve

pin 2 = video + ----------------------------------- video ground

pin 1 = video - ------/-----------------------------video +

pin 3 = power +15v /

pin 4 = ground ----/

 

pin 1 and pin 4 connect bote to video +

 

why pin 2 video ground is a don't no butt it's working on this way

[dude1234 0]

Just registered to post a conformation of this. Cant confirm the pin numbers but it is possible to get the cameras using 12v instead of 24v and sending video to normal bnc cctv units. The thing is you have to bridge the power ground/neutral/negative with the video ground to get any video signal. Even then you get video interference thru the mic. i resolved this by pulling the mics out! one solid video signal now. not sure about weather this will work with multiple cameras like this as i only have one atm. Beware the cable configuration. my colors were misleading.