ramigab 0 Posted April 9, 2013 We have a Pelco CCTV system in one of our sites consisting of the following... 1. Pelco DVR DX-8100 2. Pelco Matrix CM-6800 3. Pelco Keyboards KBD-200A We purchased HP LCD monitors to use instead of old CRT monitors as they are cheaper than BNC type monitors, for that we usually get TV-boxes that convert from BNC to VGA and get a perfect picture on our other (non Pelco) DVR systems. On the Pelco, when we connect the TV-Box to to the HP monitors we get a horribly interlaced picture and lose keyboard control, if we change the Ohm setting found on any of the channels in the back of the matrix, the picture becomes perfect but we still lose PTZ and camera control on the keyboards. Any clues ? Share this post Link to post Share on other sites
hardwired 0 Posted April 10, 2013 Pelco's Coaxitron (up the coax) control method is sensitive to termination issues, it sounds like the HP monitors have a high input impedance. Try adding a BNC "T" adapter at the monitor, with a 75 Ohm terminating resistor also on the "T" adapter. This should bring the signal level down at the monitor, and provide the proper termination for the Coaxitron signal. Share this post Link to post Share on other sites
ramigab 0 Posted April 10, 2013 Pelco's Coaxitron (up the coax) control method is sensitive to termination issues, it sounds like the HP monitors have a high input impedance. Try adding a BNC "T" adapter at the monitor, with a 75 Ohm terminating resistor also on the "T" adapter. This should bring the signal level down at the monitor, and provide the proper termination for the Coaxitron signal. Thank you Hardwired ! Your solution sounds very logical, I'll source a T connector and 75 Ohm Terminator and update you on how it goes. Is there anything else I could try out ? The site is quite far from me and it will be easier to try out different ideas all at once. Thanks again for your help Share this post Link to post Share on other sites
ramigab 0 Posted April 15, 2013 Pelco's Coaxitron (up the coax) control method is sensitive to termination issues, it sounds like the HP monitors have a high input impedance. Try adding a BNC "T" adapter at the monitor, with a 75 Ohm terminating resistor also on the "T" adapter. This should bring the signal level down at the monitor, and provide the proper termination for the Coaxitron signal. Dear HardWired, you are a life savior " title="Applause" /> Your idea of adding a BNC terminator worked perfectly !!! Great picture and PTZ control is working as it should. Many thanks Share this post Link to post Share on other sites
hardwired 0 Posted April 15, 2013 Glad I could help, hope all else goes well. Share this post Link to post Share on other sites