Interference on cheap cctv cable

[ronbo 0]

hi all

 

I brought a couple of small day/night CCD domes from............. yep you guess it Ebay. actually not bad at all but notice slight wavey lines and the more detailed the image the worse the waves are.

 

the cable ive used is not coax, as i thought i may as well take advantage of the free AV Lead (RCA)all in one as it come with it i thought it should work fine altho i had reservations due to its size of 4 cm dia.

 

ive now used coax to test and found no interference

 

you are prob thinking well "you had a problem, You've found the solution?"

 

yes but ive already installed one camera and rather not re-run in coax and seperate power.

 

any ideas what you may do in this situation

 

i thought hum bar rejecters but thats just for mains?

 

cheers

[scorpion 0]

Is it possible to attach new siamese wire (coax, and power) to the old wire, and pull it through?

[ronbo 0]

i would like to and to do it properlywith coax but i have installed the camera on a pebble dash wall and in order to have no cable showing on the pebble dash i ingeniously chiseled a line out of the wall filled with mastic and stuck bits of pebble dash onto it so now the cable cant be seen as it does look rather good even by my standards.

 

so i could rip it out and start again but would like to leave it if possible.

 

so would you say that the strands running the video are too small and may be the 12 volts are effecting the image? As when i did another job i used a 4 core alarm cable and it worked fine( ps was a local job not a proper works job)

[scorpion 0]

If the camera is mounted to a brick wall then that rules out ground loop issues.

 

From the camera to the groove where you added pebble dash from here where does it go? Can you solder the rca style wire to a proper RG 59 from that point back to your dvr?

[ronbo 0]

its standard brick. but found the problem,

 

when i tested a simaler camera with the same power supply and coax it worked fine with no waves and when i used the cable in question i had the interferance again. so that led me to think it was the video part of the cable but i got asked to check the power supply as he said, and i quote;

 

"the power supply is not very well regulated.

The ac component in what should be a dc supply is being induced in to the video"

 

so with out a fully charged 12v battery i used and old but better quality 12 v mains supply and.............................. Works perfect !! no interferance so i will change the power supply.

 

So luckly i dont need to undo my handy work too soon

[ronbo 0]

so just when i thought the problem was solved...

i only checked the day images and they was very good but on looking and the night time image the Interference has come back and im sure its worse? as the LEDs are on.

so i will need to get even closer to the camera at night and try with a battery. with all this in mind ive already ran coax and seperate power in the form of an 4/8 core to the cameras . never had problems with that before!

 

moral of the storey "It is too good to be true"