Ted

I like this, I have alot of those that I have found during repairs. Answer: This is my concern: simply telling someone new to the whole thing, "Oh, just go to 24V instead of 12V!" may be a recipe for disaster, if he doesn't realize that not all cameras will survive 24V and just blindly makes the change. And besides, voltage drop would cause the affected cameras to simply drop out, not "fade in and out" as described. If you say so.. What solutions would you suggest if the skill level of the receiver is below basic 12/24V knowledge? Anyway, another guess of mine: Are there any cameras connected to a monitor with a T- or Y-contact before connected to the DVR?

Absolutely, I'm not arguing that, the tension loss over distance is the problem with 12VDC. It is better for distances >75ft to use 24VAC and a 24VAC/12VDC converter if you have a 12VDC camera. I assume that people installing CCTV-systems know the difference between 12VDC and 24VAC.

I had a discussion a while back about setting up several wireless IP-cameras to a common access point. Has anyone here tried that? My guess is that it doesn't work because of radio interference. Each camera transmits a constant stream, so which camera will be received by the AP? The strongest. I tried to explain that it is the same thing if four guys with walkie talkies push the talkbutton at the same time and a fifth guy tries to hear what each guy is saying. But since i haven't tried it, i might be wrong. Any experiences?

I assume you have checked the video connector on the PCB. If you are using a auto-iris lens check the switch settings.

Good point 12 VDC over more than 100ft of cable gives more tension fall, which you don't have with 24VAC.

Start here: http://en.wikipedia.org/wiki/IP_camera

A video matrix solves your problem. If you are going to display the same image in all monitors you could simply loop the signal through each monitor. Or a combination of both. 100ft is no problem.

16 cameras on one 12VDC? My guess is that you have some problems with tension. Especially on the cameras farthest away from the power supply. I'd try 24VAC instead.

Agree with Soundy, cables or there might be a potential difference in the earthing (is that the correct term?). Do you power the cameras from the same outlet? Also if you have an open coupling that might connect the cable's earth to a metal object along the way could cause some tricky effects. The best is to power all cameras from the same outlet (24VAC) then you know you have the same earth on all cameras.

In some cameras you can adjust several settings with either dip-switches or by connecting it to a PC. I don't know if the frame rate is one of those settings. Does it appear the same when you watch it on site?

Ok, so even if they transmits continously, in reality they don't transmit a constant signal. The transmitters switch on and off, but quite rapidly. And in those gaps in transmissions, other transmissions occur. I guess the data is buffered in the cam and transmitted when there is a suitable moment or gap and it is all orchestrated by the switch. My background is from analog radiocommunications, that's why I was confused about several transmitters on the same frequency.

I know that is working, but I know too little to draw any conclusions on how the comparison with cameras is applicable. That's true, you can't. Unless they operate on different frequencies. They can operate in the same frequency range but not on the exact same frequency. Different channels aren't the same frequencies. Agree. Point to point linking is in many cases cheaper than wiring with fiber.

Yes I have used multiple computers to a single wireless router. The difference between computers and a camera is that the computer transmits packages only when information is exchanged. Between those packages other sources can use the router because transmission is turned off, it doesn't have a constant flow of data. A camera transmits continously. Two portable handsets cannot use the same DECT base station simultaneously, same thing. You cannot listen to two radio-stations at the same time. The only way I can see this possible is if the cameras use different radiofrequencies. I haven't tried so I can't tell for sure. But on the other hand, for security reasons, wireless is not optimal. Maybe directed antennas as a link between buildings, connecting a cluster of cameras through a switch to a server. So I still wonder if anyone tried connecting, for exampel, four Axis 207W to a common accesspoint. Theories and reality are not always in the same league

To me it seems as there is a setting either in the camera (does it have full rate into the DVR?) or a server setting that reduces remote fps to save bandwidth. Since it has been working with the other colorcamera and with the B/W camera it seems as it is the camera that doesn't deliver full frame rate. Maybe some MJPEG/MPEG4 setting?

It could be interferences from a lighting source close to the cam or a high current cable close to the cam or cam-cable somewhere on the way to the DVR. Maybe a DECT base-station close to the camera, unlikely though. Are there any joints on the cable? Try to move the cable on a few locations and see if the interference changes in any way.

Hi, I recently lost a deal to a competitor because he could deliver LPR without IR. Losing a deal is one thing but when it's because I lack in knowledge I have to do something about it. Then I found this forum and hope that somebody here know "the secret". The camera should deliver a readable image of a license plate at night with street light as only light source and head on with headlights on. I think he used Axis 221 mounted on a pole about 12' up looking fairly straight down and a little offset to the side. Distance from the pole's base to the car is about 7-10'. Anyone here ever done that? What would the camera settings be? Shutter speed etc? Having the camera looking down this way reduces the backlight problem I guess, but still I have to have enought light at the plate so that it reflects some to the camera. Calling my competitor to ask, isn't an option

Did you check with another split? Edit: I just saw that you use an RCA-split. Let me get this straight. First camera, camera connected to coax with BNC. Other end, BNC to RCA converter, then RCA-split. The split is a female with two male on short cables? The male to TV. To TV direct or via extension? If this is your configuration, I'd use a BNC T-split and BNC-RCA Adapters at the TV-sets. This would involve two coax-patches, from BNC-split to BNC-RCA-adapter. It could be that your RCA-split is 50 ohms and parallell-coupled it could screw up the picture like your description.

Agree there VST_Man, I always use a two-cam setting on sites like this, where one is dedicated LPR. No point in just knowing which car they had... In more planned crimes the plates are probably stolen anyway.

I have used T-split and distributed the signal 300' on several sets with fairly good picture with RG59+2 copper cables. It's not optimal, the best is a distr. amp. for sure. But you say you cut the ends on the prefab cable, which means you have pressed a new BNC at both ends, are you sure this is done correctly? Also when you had the excess cable, was it rolled up in a coil? A split and a coiled cable of unknown impedance and quality and perhaps a short in a BNC, you could have some problems with the image quality.

Oops, forgot to mention, there is a stop involved. The setting is at a gate, an entrance to a loading area. The big test should be right now when snow and dirty roads smothers the plates.

Hi I'm Ted, new here. Just found this site of knowledge which looks very good. Very good idea to gather a bunch of skilled people. I will contribute with what I can. See you!

Actually it has already been installed and the customer says he is pleased with the system. Haven't seen it myself though. I'll ask him if I can pay him a visit just to see for myself. But I've also heard of others who have done the same thing, but with IQeye 753.

Just be sure to mask the areas of no interest for motion. Pointed down right in front of the door won't give too much disturbing motion.