View Full Version : messing up a security camera

02-11-2015, 06:07 AM
Here's the scenario, although it could be easily changed. Video camera placed over janitor's closet, which does not cover the actual door to the closet. Character breaks into the closet and has a few minutes to mess up the camera. Through the wall and going into the closet are a hard-wired power cord and a co-axial cable feeding the video into the viewer.

Simple solution is to cut the power cord and kill the camera. Character would prefer something subtler and producing interference.

One thought is an x-acto knife jabbed through the wire. Another thought is a paperclip heated with a cigarette lighter jabbed through it. Preferably then removed so as to leave no trace. Third thought is a magnet placed against the cable. Fourth thought would be a corrosive in the janitor's closet.

Problem is I don't know if any of those will work. I also don't know if there's another way to do this. Method has to be something easily acquired.

All help is appreciated.

Jim Clark-Dawe

T Robinson
02-11-2015, 06:15 AM
Shred the coax and leave a dead rat in the closet.

Open the closet enough to get his arm out, spray the lens with something that obscures the lens, but evaporates after a certain amount of time.

Remembering that it may feed to a DVR and there may be other cameras that cover some of that sector

02-11-2015, 06:27 AM
How long does the camera need to be down?

I'm told that lasers aimed at the lens can overpower the light sensor. Depending on the power of the laser, it could perhaps completely burn it out.

Dennis E. Taylor
02-11-2015, 06:29 AM
The heated paperclip was a nice idea, but leave it in (or break it off at the surface) That would effectively short the coax and pooch the video output.

02-11-2015, 07:52 AM
Simple solution is to cut the power cord and kill the camera. Character would prefer something subtler and producing interference.

Why? What's the point? Seems pretty silly to me. Makes me think of the hilarious moment in the Austin Powers movie where Dr. Evil is explaining to his table of evil cohorts the elaborate plan he has for destroying Austin Powers, who is sitting there, bound. Dr. Evil's son, Scott (played wonderfully by Seth Green), gets exasperated and says, "Why don't you just shoot him?"


02-11-2015, 08:15 PM
The question I'm asking is why would there be a security camera that is not pointed towards the entryway? Isn't that the point of the security camera?

If you are working with a camera on an IP connection, it is a simple job if you have gloves (if you don't want any incriminating evidence.) Analog cameras are a bit more difficult because of the coax connection, even if you have gloves. That said, analog cameras are getting much rarer these days. IP cameras have the benefit of carrying higher resolutions (1080p, 1920p) than analogs which only go up to 320 lines.

02-12-2015, 06:52 AM
T Robinson -- I like the rat, but too much set up needed.

Cmhbob -- Lasers work, but people are likely to notice if you do it in public.

Angry Guy -- Right at the moment, I'm going with the paperclip and having him break it off.

Blacbird -- Police will figure he probably did something, but cutting the wire will end up with a notation by the guy who fixes it. A cable with interference could be swapped out without ever having a notation of why there was interference.

Xelebes -- Camera will record him approaching, but the idea is to have no record of him leaving. While in the closet he's going to change and doesn't want the police to have an idea of what his changed appearance looks like. A camera with an IP connection doesn't have a cable, does it? He needs something that would be in the closet to work on so the public doesn't see him. This camera would be in a public transit building, and these guys tend to be slow to update to current technology.

Thanks for all of the help.

Jim Clark-Dawe

02-12-2015, 08:48 AM
You'd be surprised what people will and won't notice. I've played with my green laser pointer in public before and few people really take notice of it. I'd bet I could put the dot on the lens pretty quickly before anyone really noticed.

02-12-2015, 09:21 AM
IP cameras use crystals like your typical LAN cable.

Public transit? Hm. The camera is going to be outside of the closet since there is only one entryway for that closet. This depends entirely on design but a camera like that is going to be in a pretty open space where foot traffic is encouraged and vandals are discouraged to mess with the domes. Disabling these cameras is going to require some disassembly and will require a ladder (3 - 4 m ceilings here in Edmonton, for example.) Cabling would not be exposed unless the design of the facility is of a brutalist design. As for lasers, they might work through a dome but they might not.

Just some things you have to consider.

Drachen Jager
02-12-2015, 10:30 AM
One thought is an x-acto knife jabbed through the wire. This will either do nothing, or kill the signal entirely. Another thought is a paperclip heated with a cigarette lighter jabbed through it. Same. Preferably then removed so as to leave no trace. Then it would turn the signal off, then back on (or do nothing at all). Third thought is a magnet placed against the cable. Because... magnets? Fourth thought would be a corrosive in the janitor's closet. Why? How would he use it?

Problem is I don't know if any of those will work. I also don't know if there's another way to do this. Method has to be something easily acquired. None of them will work as you seem to want.

You seem to think damaging the coax shielding will cause massive interference. That isn't so. You'd need to strip a good stretch of the shielding for this to work.

None of these would accomplish anything that unplugging the coax couldn't do more simply.

02-12-2015, 05:53 PM
What I'm working with is an actual hallway in a transit building, although it isn't in the physical location I want.

Hallway is cinder block construction on both sides. One wall is a solid exterior wall. Interior wall has janitor's closet and restrooms along it, with a minor entry/exit door on the end by the janitor's closet.

Camera was added after 9/11. Camera is mounted on bracket attached into cinder blocks, and back of camera sits about three inches out from wall. Ceilings are solid, so they drilled through the cinder blocks to run the cables into the janitor's closet.

Janitor's closet is key entry, but nothing very complicated. Easily picked open. Character will then shut the closet door. He can't work on the camera itself, because people would see him in the hallway. Picking a lock can be done so it looks like someone fumbling with keys.

Once inside the closet, there's a stepladder for the janitor to use. The wiring runs out from the wall and along the ceiling disappearing on the back side of the closet. So the character has basically five to ten minutes alone with the wiring.

Coaxial through the closet has no junctions, although I could re-arrange the wiring to put in a junction. I'm not sure why there would be a junction, though. And that would make my character's life a bit too easy.

Drachen -- The reason I'm asking here is I'm not sure of how complicated it is to muck up a coaxial cable. Basically I'm looking at a Macguver solution.

Best of luck,

Jim Clark-Dawe

02-12-2015, 06:59 PM
The paperclip option likely won't work, even heated. The problem is that the cable includes a copper sheath. It's usually very fine braided mesh, so you *can* pierce it. But it's also usually several layers thick. So you're pushing it given the time constraints you've mentioned.

BUT, if you take that paperclip and insert it, then have a small electric oscillator (i.e. a "white noise" signal generator), you can use the paperclip as a kind of antenna to receive the oscillating electrical signal and induce noise into the cable.

There's all kinds of stuff I've left out of that. However, I think that's weird enough, and yet plausible, that it'll "MacGuyver" just fine. And since you're not piercing a metal-shielded cable, you can preassemble. The oscillator can fit in his pocket and run for a short time on batteries. Pierce the cable somewhere not easily seen, and leave the oscillator in some nook or cranny of the closet.

And the oscillator could be made to look like a thermostat. The building inhabitants may not (initially) realize that a janitor's closet isn't normally temperature controlled :)

Drachen Jager
02-12-2015, 11:13 PM
How about this? Handheld stun guns are readily available and fairly cheap in the US. If he took one of those, stripped the insulation of the coax and placed the prongs on either side of the stripped wire, then taped the button down, that would royally screw up any signal. The batteries wouldn't last long, but you could probably get a few minutes of signal interruption out of it.

02-13-2015, 12:15 AM
All right, some questions you are going to have to answer before you put that in your story:

1. How does the individual know that a cable provides access in a room? Has it been scoped before? Does he know where the camera is beforehand. How much time is affording himself in surveying the facility for the locations that he is going to need? Because if this is bang, bang, boom, I'm going to tell you that he will likely not know which IP or coax cable leads to what. The cables overhead are going to be bunched overhead so as to avoid the other utilities that are passing overhead (electrical must never be in contact with gas lines.) What is likely going to happen is that he is going to have to guess with the door opened so that he can trace the cable.

Now, this may be a bit trickier than you imagine. A single strand is going to be tucked pretty hard to the wall or going to run through conduit. I can easily imagine that the janitor room is also being used as a utility room so there will likely be junctions or a router box that you would have access to.

Messing with the router would be the easiest thing to do.

02-13-2015, 03:01 AM
Xelebes -- This tends to be sloppy add-on wiring. I've seen a couple of these jobs and it's basically a drill through the wall, feed the wire through, and tack it to the wall. In the big cities they do this right, but the smaller regional transportation stations and Greyhound stations are cheap and are barely up to code.

I'm trying to limit myself to what's available at the store at these smaller stations, although I've got to admit to really like the stun gun approach.

I like the idea of a paperclip, a piece of wire, and a battery-operated electric razor. I think an electric razor has an oscillating electric motor. I've seen cheapie versions available at Greyhound terminals. The reason I like this is he turns the razor on and the screen picks up interference. Eventually the battery will run down and the interference will clear up. Minimum wage guy at the terminal figures problem is solved and there's no sense in putting in a repair order or might not even note it on his or her log.

It would be obvious to someone who looks at the wiring, but with the time constraints, I don't think he can come up with something that avoids detection.

Thanks for all the help.

Jim Clark-Dawe

Drachen Jager
02-14-2015, 03:21 AM
The motor in razors don't oscillate, there's a sort of gearbox to change the circular motion of the motor to an angular motion for the razor blade. The motor is DC and operating in a fairly steady state. There would be a little static created by the brushes, but not much. Probably not enough to influence a camera.

02-14-2015, 05:24 AM
Crud. Is there a commonly available oscillating electric motor that would cause interference?


Drachen Jager
02-14-2015, 06:27 AM
Electric motors generally just go round and round, anything else is just asking for mechanical problems. Something with an old-school buzzer maybe, but those haven't been commonly sold in 20-30 years.

If he has time, buy a portable music player, strip the headphone wires, strip the coax down to the middle copper wire, put one headphone wire on the centre cable and one on the sheath, turn some noisy music on... I think that would do it.

With 5 years of electronics repair experience behind me and a very thorough education on electronics generally (though not cameras specifically) I'd buy that if it was in a book. I think you'd be hard pressed to find an expert who can tell you my suggestion won't work without experimenting with it themselves.

02-16-2015, 05:41 AM
I went with the MP-3 player idea. It's credible, janitors forget their MP-3 players all the time, and the rest of what he needs is also likely to be in a janitor's closet. It will run for a while and then the problem goes away. There's a good chance no repair order ever goes in. It's not untraceable, but considering he can't plan this ahead of time, he's not going to get untraceable.

Thanks for all of the help.


02-16-2015, 07:07 AM
I see you've got a solution, but I wanted to drop this here for future reference. It's a 2002 paper where the writer did some actual hands-on research.


There's also this link, with an example photo:

The upshot seems to be that yes, the camera can be damaged, but it's more likely to be dazzled, and require some way to keep the laser aimed at the camera.

ETA: A Google search to get you started: https://www.google.com/search?q=laser+pointer+vs+camera

02-16-2015, 06:43 PM
Forget the paper clip and use a staple gun or a screw. If the cable is just pushed through a block wall, a hard tank on it can pull it out of the camera. Either the power or the coax can separate from the connector. Pull the cable down a little, then yank on it and hang a broom on the dangling cord. Just a bumbling janitor then.


02-18-2015, 12:59 AM
An infrared LED up close should overexpose the image. Really not following the limitations.

02-18-2015, 11:27 AM
Is the location he is breaking into a no fly zone after a certain hour and is the camera recording only or is there a
surveillance crew watching from a different location? More than likely a second camera would be pointing at the closet from the other end of the hall. If the company is not cheap there will be exterior cameras as well. If it is a no fly zone and being watched live the MC's presence on the property would get a monitor's attention. I/Os would be sounded first and if ignored the monitor would dispatch on the MC. So by the time the MC cut the power, a tracker for the company and the police would be in place. Unless the monitor missed it or it's not a live view security system. Even if it's not live view the MC would probably have to take care of more than one camera.