Parallel Fog Type Lines Moving Up And Down Screen

[Map Security]

it depends how close you run your camera cables to the large cables. my advice is stay at least 4 mts away or more if possible but if not you could enclose them in trunking

regards

colin

In some areas I will be 1mtr away from SWA power feeds.....Anything I can do to "neutralise" interference should this happen?

[Guest]

try to not get them touching and if possible keep them bunched together. other than that if anything occurs then give them a humbug (black and white sweet) and tell them if its no better in the morning then go to see a doctor.

( old hand would be proud of me!)

I`m saying nothing

[jizzer]

how many cams are running off the psu, and what is the current rating of each cam also the current rating of psu, ie is each cam got a psu of its own or do thy share the psu together

colin

This is the PSU I am using but I am not using battery back up at the moment

http://rswww.com/cgi-bin/bv/rswww/searchBr...e&Nr=avl:uk

Running 3 cams from this unit 1Dome @ 190Ma max and 2 Baxalls cant remember consumption but low current under output for this unit .Voltage measured at Dome 12.4Vdc

[jizzer]

but have you tried a battery or do you know its someting else

Have not had chance to try battery yet

[Rich]

its likely to be the PSU, possibly the capacitors failing, could try a cheap 12V PSU or battery on each camera and make sure that the fault clears, if so then you can probably get the capacitors replaced by a local TV Repair shop or the likes.

[Gopher]

I've seen this effect and it was caused by 1 of 2 things.

1st was a coax issue with "up-the-coax" telemetry but you don't say if you use that or not and it's a case of seeing if there are options to adjust options the exact ones escape me right now.

2nd was the actual modulator was sending feedback up the coax and into the dvr, have you tried it with just a monitor connected to the DVR output without the modulator attached?

It's 2 more things to check anyway.

[jizzer]

not always, have you tried the battery idea?

finally got my *rse in gear and tried the battery and the lines dissapear!!! does that mean I need a Hum block?

If so where abouts does it fit at DVR end? I cannot understand why this has suddenly occured as the system has been running for six months with no problems.

UPDATE>>>>>>>>>>>>>>>

Just checked the PSU it has a voltage output trim pot turned I turned it down to 8.5Vdc and the other cams displayed the parrallel line fault it would not then ramp back up to 12V so i powered down PSU and On powering back up the psu ramped up but maximum Volts I can get measured at PSU terminals with cams connected is 11.5Volts is that enough.

By powering with the battery what does this prove is it a Hum problem or the PSU?????

[arfur mo]

maybe the PSU regs have gote a bit leaky, then you get AC ripple in the 12 volt line, or the resouvior cap has dried out, happens on cheapie psu's quite a bit. it's not the end of the world to swap it out, if your wrong you got spare for next time.

if your psu is remoted from the camera, you could fit a 2000 - 3000uf (35+ wkv) electolytic cap to the camera to smoothe the supply.

the 'humbug' (isloating transformer) go's at the DVR end, it will reduce signal so depends how strong your signal is, swao the PSU out as if its the problem the humbug won't help, it is the problem then you have save the cos of the humbug.

regs

alan

[jizzer]

the cameras need between 12 vdc and 13vdc regulated. as youver tried it on a battery it has not earth path but a psu does. change the psu and that should cure it. sounds like theres not enough voltage to run the camera.

colin

Yes think your correct the baxalls which are OK probably have a better voltage tolerance than the dome just connected the dome to the psu on its own PSU dragging down to 10.3 V and camera wont display picture connect back to battery all ok!! Looks like a trip to Maplins in morning

[jizzer]

as with everything you gets what you pay for, dont skimp on your psu

I didnt this is a