ilkie Posted January 2, 2007 Posted January 2, 2007 Have you tried your test monitor on the input to the DVR? If the sync pulse is distorted the test monitor may produce a picture but the DVR may not. An oscilloscope will confirm this. Regards Ilkie
Taylormade Posted January 7, 2007 Author Posted January 7, 2007 Have you tried your test monitor on the input to the DVR?If the sync pulse is distorted the test monitor may produce a picture but the DVR may not. An oscilloscope will confirm this. Regards Ilkie Thanks for all your posts Guys, you have given me a good selection of possible solutions, Ill try the easiest 1st, Double up the cores, then probably up the voltage to about 14v. P.S im not using baluns, i've run individual RG59 to each camera and wired the power off cat5e in parallel. Will put a post on when ive resolved the problem to let you all know how it went Lee
nikko Posted January 8, 2007 Posted January 8, 2007 Have you tried your test monitor on the input to the DVR?If the sync pulse is distorted the test monitor may produce a picture but the DVR may not. An oscilloscope will confirm this. Regards Ilkie I'd personally agree with ilkie. Anything which processes a video signal can be quite particular as to what you try to input. Try taking the RG59 out from the DVR and stick it straight in the customers monitor. If you get a picture when you bypass the DVR then I would almost guarantee the sync pulse is too low from the camera. A peak meter is cheaper than a scope to confirm this. What part of the world are you in? If you're not too far I would lend you my scope/peak meter. I went up into the attic...I found a Stradavarius & a Picasso. Unfortunately..... Stradavarius couldn't paint, and Picasso made a shocking fiddle. My Facebook page...http://www.facebook.com/home.php#/profile.php?id=1279556853&ref=name
Guest Posted January 28, 2007 Posted January 28, 2007 * The same power supply is also powering a couple of other cameras which are working fine What is the psu rated at? It sounds to me your overloading it. Why not get a 4 way split load and feed the cameras individually? This has been a problem in the past and the split load psu solved the issue.
arfur mo Posted January 28, 2007 Posted January 28, 2007 you could send 24v from the origin, and at the camera end have a 24 to 12v regulator feeding the camera i agree with you spider, imo it's the best way too, if several camera's share the same PSU, increasing the voltage may damage the 'local' camera's if not straight away, then will shorten their life over time or fail during a hot spell. regs alan If you think education is difficult, try being stupid!!!!
Guest Posted January 28, 2007 Posted January 28, 2007 i agree with you spider, imo it's the best way too, if several camera's share the same PSU, increasing the voltage may damage the 'local' camera's if not straight away, then will shorten their life over time or fail during a hot spell. regs alan So what's wrong with splitting the cameras up and each having a separate (split psu) supply, then in case of failure you can see the problem right away? Think you`ll find thats the best solution !
Guest Posted January 28, 2007 Posted January 28, 2007 how come people are saying its voltage here? if he tested at dvr end and nothing then tested at the camera end and a picture then i wouldnt say it was the voltage i would that it was a problem with the coax cable. or am i barking completley up the wrong tree?? The tree you want is somewhere in the distance.
ilkie Posted January 28, 2007 Posted January 28, 2007 To check the coax (or any transmission system) the only true to to set the circuit up is with a pulse and bar pattern generator at the camera end and a 'scope at the DVR end. There is no other professional way of checking the transmission line. Ilker
arfur mo Posted January 28, 2007 Posted January 28, 2007 So what's wrong with splitting the cameras up and each having a separate (split psu) supply, then in case of failure you can see the problem right away?Think you`ll find thats the best solution ! hi OH, not wanting another 'tamper' bun fight with James and Paul (which i won anyway ). i don't say just upping the voltage wil not work, but using local regulators is imo a more ellegant solution. if you have a split psu they are only splitting the supply by fuses. yes y u will have diagnostics via these fuses but a camera on 20 feet of cable will be subjected to the higher 'corrective' voltage perhaps 16 - 18 volts, needed to drive the furthest camera/s. depending on ambient temperature camera's draw different current when hot gainst cold (so voltage will alter). for a voltage regulator to work properly it needs around 17 - 20 input voltage to 'regulate' down to 12vdc. so then 2 regulators are needed, (or one local regulator from 2 psu's). a brutal way is fit a high power zenor diode and 2500uf res cap to the local camera, fed by 100 ohm 10 watt resistor. regs alan If you think education is difficult, try being stupid!!!!
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