holdendp 0 Posted June 24, 2004 I bought a GV-250, it's nice but when I get 4 cameras plugged in the image instensities start to oscillate at around 1 hz, it trigger the motion detection. Is this a problem with a cheap card or cheap cameras? Thanks, Dave Holden Share this post Link to post Share on other sites
CCTVmofo 0 Posted June 24, 2004 it is most likley your card. DVR cards have a tendency to react poorly when using less expensive cameras. They also do not like it when you are using color and black and white at the same time. Additionaly, if the computer that you are using it with is old you may also have problems. If it is in your budget i would recommend a 4 channel stand alone dvr or even a single channel with a quad if you really cant break the bank... Share this post Link to post Share on other sites
AVCONSULTING 0 Posted June 24, 2004 You might also have ground loop problems on one of the cameras. All sorts of things can screw up a DVR because they are very sensitive to line problems. Are you using 12vdc cameras and if so how far are they away, what type of power supplies, connectors, cable, etc. Share this post Link to post Share on other sites
cctv_down_under 0 Posted June 28, 2004 Because a PC card works with a multiplexing chip it is important to choose the inputs carfeully if mixing colour with B/W, for instance a 16ch card may mux channels 1, 5, 9, 13 so putting your B/W cams on those ports prevents overshooting, ther is also a difference between analogue voltage and Digital recieving.. the best video signal is recieved at 1volt peak to peak but DVr cards tend to prefer 1.1 volt peak to peak, most good cams do this anyway but cheaper cameras can be a problem as they can be short on the required settings. It is more likely that you have a ground loop or have failed to load direct X 9 before intstallation of the software for your card, this results in picture bouncing (marginally) which can result in the representation of actual motion events that do not occur, you can adjust your system for the gain differencial in the software if supported or switch the gain control setting on your camera to AGC (auto gain control).. i would bet it is more likely a ground loop but under voltaged cameras can have issues aswell and this tends to happen when too many cameras are on one power supply or the power is not filtered cleanly or regulated. I hope this helps GC Share this post Link to post Share on other sites
