Pre made CCTV cables (chopped off BNC)

[SD60659]

Hi guys, new here and in a bit of a pickle. I've done several CCTV installs over the years, so not a total noob but I'm stuck. Adding another camera to an existing system I installed, the guy bought all the kit himself and everything is fine bar this new camera. It's a 200M run of PRE MADE cable, 2x 100M spools, not shotgun cable. The really thin skinny stuff with the BNC and power supply connectors pre made, here is a link to the cables https://www.ebay.co.uk/itm/5M-100M-...hash=item2cb630ffb9:m:mPPT5wfdGUCjDavJHBHd7PA

So what I've done is join the cables together to create a 200M run, power side was just a simple case of plugging in (male to female) but the signal side obviously had female BNC to female BNC. In the absence of the appropriate coupler, I just chopped both BNC off and joined the wires, fiddly and not ideal (I am aware of this) but it isn't working. Camera has power but zero image. I've read up on this, including a good thread on here, some are insistent you CANNOT do this and others say you can. Is there a reason WHY you can't do this? Is it the fact I've joined the cables and done away with the BNC's? I'm stumped as to why that wouldn't work. Or is it just too long a run? Any help would be greatly appreciated and yes you may all feel free to call me names for chopping the BNC's off, but I'd love to find out if this absolutely CANNOT work or if I've just done it wrong?

I should also mention that the camera does work as I tested it before hand.

 

[Tigercubrider]

Have you bleeped the cable through? You could have failed in the connection or reversed the cables

It's possible that the camera can't send a signal down 200m of cheap cable. It might need an amp.

You should have used a barrel connector

 

[SD60659]

Thanks for the reply and yes I know I should have used a barrel connector. The two cores inside the signal part of the cable are colour coded so there's no mix-up there :/
I might see if I can (somehow) make the connections "better" but during all my fiddling about I haven't had so much as a flicker or terrible image, which I would sort of expect to get, but absolutely nothing

 

[flameport]

Signal is being degraded to the point of nothing by the substandard grossly too long cable.
Or volt drop on the cable is excessive to the point that the camera doesn't work properly.
Probably both.

In future, join the 21st century and fit IP cameras with POE instead.
And don't ever install tat that customers obtained from ebay. It's always guaranteed to cost 10x more in wasted time than buying proper equipment would have.

 

[secureiam]

what camera, sounds like the connection to your new fitting isn't good assuming the camera was good to start with.

what bothers me is you cut a connector off and replaced it, what did you cut of and what did you replace it with?

 

[Harry Bloomfield]

Have you tested the camera without the long BNC, but with the long supply cable? does that work?

If that works, I would suggest the problem is the 200m long BNC cable - I would be very surprised if any such camera could drive an image over that distance anyway..

 

[SD60659]

I haven't tried that test no, I don't see how I could do that with these pre made cables (see link in first post) - I don't normally use these but this is what he bought so I thought I'd give it a whirl. There's definitely power to the camera, although there could still be voltage drop as one poster pointed out. I'm definitely leaning towards it being a problem on the signal side of it, either my connection just isn't good enough (which I'd be surprised about seeing as I'm an electrician!) or it's just not going to work over a 200M run.

I tested it with 100M run and it worked fine, so I just assumed it would be ok at 200M (yes I know that's DOUBLE the distance!)

 

[secureiam]

just power locally if possible?

 

[Harry Bloomfield]

I tested it with 100M run and it worked fine, so I just assumed it would be ok at 200M (yes I know that's DOUBLE the distance!)

I didn't realise you had tested at 100m. If its fine at 100m, I would expect some sort of image at 200m

In that case, not signal at all sounds like not enough voltage at the end of the cable due to volts drop. Is there any way you can check it. Likely the camera will work OK at one voltage, then drop completely out as the voltage decreases - which is what I not suspect.

 

[SD60659]

I didn't realise you had tested at 100m. If its fine at 100m, I would expect some sort of image at 200m

Yeah that was exactly my thinking tbh. I can't power it locally (impossible due to location) but I could meter it at the camera to see how much juice is there. It definitely has power to the camera, but like you say it could have dropped to an insufficient level for function. That'll be tomorrow's test! Thanks for the reply

 

[Harry Bloomfield]

I don't know what grade of coax you have, but RG59 is suggested to support video upto 200m.

 

[SD60659]

http://rover.ebay.com/rover/1/710-5...hash=item2cb630ffb9:m:mPPT5wfdGUCjDavJHBHd7PA

This is the cable. It's not actually coaxial cable. Unshielded copper conductors, no air gap. They're just ready made extensions compatible with the system he bought, I've used them in the past on Swann systems etc but never more than 50M. First time I've tried to push it past that. Most of the time I go for wireless if it's long range but good wireless kit is ££££

 

[Harry Bloomfield]

I would expect that to be very lossy..

 

[Sally2000]

200m of that thin stuff will be a huge voltage drop, especially after dark with the extra current draw of IR leds. And it's vulnerable to being stressed and fractured during installation.

It's just not worth penny pinching on cables. As said on here so many times - buy cheap, buy twice.