Guys i currently have some typical box cameras hooked up throught my store ussing siamese cable. I want to put more cameras in but i don't have enough cable to run all new lines for the cameras that i want to put in. Is there a way that i can splice into the video and power from the other cameras? i was thinking of a switcher but i don't think that will work since i need to be able to :switch" between the cameras from my office. Any thoughts on what i can do??

Are you saying you don't have anymore wire and you need to buy more or there is no more room to run the wire?

If you are using RG-59 it is one camera per wire. If your using Cat5 then you can have one camera per par of wire. So you can have 4 camera on one Cat5 wire. This is without power.

If your using IP cameras you can use switches and you can have many IP cameras over one cat5 (trunk wire). Another advantage of IP cameras.

Their are various options you can use.......

You could fit a DuoLink (made by SNT) This will send two video feeds down one cable then split it back into two at the DVR.

You could use convertors to turn the coaxile cable into a Network cable, stick a router at the end and use IP cameras

All these are rather expensive compared with home running new cables !