The RZ-3 appears to be an older model made by Iteris, but most the ones I have still work fine. The ones that don't either were ruined by moisture leaking into the case or had a bad power supply. The camera runs off 120/240 VAC which is supplied through the round Deutsch connector at the rear of the camera. Inside there's a switching power supply that provides 12v to the electronics. Per Iteris, they had solar power in mind so I suppose the camera could be powered by 12v DC directly bypassing the power supply.
Closeup of the Deutsch connector with pinouts:
This "Deutsch" connector is evidentally proprietary, I wasn't able to find one anywhere except through Iteris. They gave me this instruction manual on them that gives a little more info on it if anyone's interested. Turns out they want $40 for one matching connector (that comes with a BNC connector too), so I just soldered and shrink-wrapped the power wires directly to the camera.
5 of the pins are unused, otherwise it's pretty simple. The big pins are hot, neutral, and ground, and 4 of the top small pins run the zoom and focus. Zoom and focus takes 12 VDC, and the polarity determines whether it's zooming/focusing in or out. Once the zoom and focus are set where you want, of course there's no need to connect the other pins. It can also be manually adjusted if you slide the camera out of the case.
The spec sheet from Iteris for the newer RZ-4 can be found here, but it's very similar to the RZ-3.
A BNC connector is used for the video connection and I just used 75 ohm CATV coax to run from the camera to the capture card. The format is of course NTSC so it can be hooked directly to any TV as well. Mine is running through about 90' of RG-6 without any signal degradation.
Any capture card would work fine, I went with a Sabrent TV-PCIRC tuner mainly because it was the cheapest card supported by Linux. If you don't have video4Linux (a host of video card drivers for Linux), you'd better get it here and there's a ton of good information about supported hardware and getting it running there too. Getting it working will probably be a bit of trial and error since Sabrent seems to change the exact details of the hardware around from time to time. I've had good luck with card #67 for my PCIRC.
I've recently installed 2 Sabrent TVFM cards, and have had good luck with them as well. The saa7134 drivers have a card # specifically for this, card 42 (unlike for the PCIRC, which just "happens" to work with the card # for a different card). They're both the same price from TigerDirect, so I think the TVFM might be a little nicer, but time will tell. So far I'm happy with both :-).
Once V4L is compiled and installed, shut down the machine and pop the card in. It'll try to auto detect, but like the article on the V4L wiki says, the newer Sabrent cards don't have an EEPROM so you'll have to manually figure out what card it is and then load the driver with the correct parameters. If you check dmesg (or whatever the bootup log for your system is) it should say what card was auto-detected. Chances are it's just the generic one, so use rmmod to unload that. The Sabrent cards have an saa7134 based chipset, so check out the saa7134 cardlist in the V4L tarball to find which card # corresponds to your card. For the PCIRC card, there isn't any specific card # that matches it, but it seems like card 67 works quite well. As mentioned before, the Sabrent TVFM card is # 42, and that worked right off for me. The tuner shouldn't much matter since we only need the composite input, though for the record I'm using tuner=17 for mine. Something like this should get you going once it's all up and running, substituting the correct card # of course.
Once it's working, you'll want it to load on bootup for next time. That's kind of specific to each system, but for Debian-based systems you just add the module to /etc/modules, and the corresponding options to /etc/modprobe.d/options.
One more thing I feel is worth mentioning, since I had a heck of a time finding it, is specifying options for multiple cards. Everything's the same, but use commas to separate the options; ie, modprobe saa7134 card=42,42 tuner=17,17 if you had 2 TVFM cards.
Now assuming that all worked, there should be a new video device in /dev. Next install xawtv if you don't have it; it's good for testing and has some very useful utilities packaged along with it. Once that's done, run v4lctl -c /dev/video0 list to see some of the details about the card. That should give something like this:
Now we'll setup webcam. This will grab a video frame from the device at a specified interval and save it to a folder. Webcam is pretty simple too, read the man pages if you need help. here's what I came up with:
Something that wasn't made very clear in the man pages is what the "input" parameter should be set to. If you look in the v4lctl list output, in the "Comments" column, it gives a list of possible values for the input for that *particular* card. We want the composite one obviously, but this is different for each parameter you can load for the card, so use v4lctl list to get the right one. Webcam won't be able to start otherwise. Now go to the image location in a browser and see if you've got a good picture. If not, unload the modules and try a different parameter. Don't forget to do a v4lctl list and modify the webcam config file to match that.