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Posted By: junkbox RJ11(?) to BNC adapter - 06/05/09 10:41 PM
Hello all,
I'm dealing with an existing camera setup, older Philips B/W cameras and recently purchased a new lorex DVR/network...anyway, the inputs on the DVR are of course BNC, I'm looking for an RJ11 to BNC converter, but my concerns are:

1. is there a standardized pinout for those rj11 ends? Mean to say would a generic rj11 to BNC converter such as this https://www.cctvoverstock.com/cctv2.asp?Model_ID=473&Task=Detail work OR

2. are the pinouts proprietary?...it's an old Philips(Bosch)VS23645T system. the pins are straight through (no Xover).

I don't want to spend $30 a piece (not really my money anyway) on these if they're not going to work.


thanks
Posted By: rustynails Re: RJ11(?) to BNC adapter - 06/05/09 10:58 PM
Not sure about those but you will need to break out the pairs. If they are 6p6c, 1 pair is used for video, 1 pair audio, 1 pair for power. I have some that i have used in the past and will check to see the make next week.

Its really a pain in the ass, and you might as well sell them cameras also and just do it right from the start.

In fact we had a customer just recently wanting to use the existing cameras which had a 6 pin DIN connector. I quoted them a whole new system and never heard back. Oh well.
Posted By: junkbox Re: RJ11(?) to BNC adapter - 06/05/09 11:22 PM
to the existing monitor, it's only 4, the power is split off at a junction to a hardwire box tha t powers the cameras and has a backup battery. talking to Bosch today they USED to sell a unit VSS7903/00T https://shop.ep-mediastore-ab.de/bosch-vss790300t-interface-pi-137242.html that did this job nicely...unfortunately Bosch doesn't have any left.

my real question is, was that "RJ11" pinout a standardized thing or not?
Posted By: junkbox Re: RJ11(?) to BNC adapter - 06/08/09 11:00 AM
As a follow up and for posterity's sake, the above adapter: https://www.cctvoverstock.com/cctv2.asp?Model_ID=473&Task=Detail does NOT function with the Phillips pinout on their RJ11 cameras...I'm just going to get some BNC cameras for the new DVR. Thanks again

-jb
Posted By: sph Re: RJ11(?) to BNC adapter - 06/08/09 12:34 PM
Thre is a CCTV wiring nomenclature that uses UTP cable and associated 4-or-6 position connectors. It is often refered to as RJ11E altough no part I know of is "Registered" with anything. Also, some manufacturers use 4P4C connectors others 6P6C, and yet others 6P4C.
It's a mess.
But, it's a cheap entry-level DIY solution, rapidly being replaced by more standardized (Category-type) cabling and connectors.
I do own a RJ11E system at home. After a bit of tweaking, I managed to have it run over cat5e cable that was already installed. Not sure I would bother with this again, if I had to.
As for the Bosch: their RJ11E uses 4 wires (audio-video-control-power), in 2 pairs, with the pairs wired side-by-side. The RJ11/BNC adapter you linked will NOT work. The proper part name btw, is "balun", as it joins the BA-lanced UTP cable to the UN-balanced coax cable.
Posted By: junkbox Re: RJ11(?) to BNC adapter - 06/08/09 01:30 PM
oh, so using any Balun, I could in theory wire it using audio and video only? is it worth it though?... i dunno cameras are cheap enough now, lorex practically gives them away.
Posted By: sph Re: RJ11(?) to BNC adapter - 06/08/09 01:43 PM
Well, in theory, everything works smile . The Balun just matches the electrical properties of different gauge/material wire. (At least it's supposed to).
Personally I'd forget the experimentation and get new cameras. I only tweaked my system cause it's mine and I had a couple of lazy Sundays.
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