Some CCTV DVR’s will allow you to record audio as well as video. Recording video involves running a coax cable from your camera to the back of a DVR. Recording audio is a little different. There are two methods that I recommend for connecting a microphone to your DVR. First, be sure that your DVR has audio inputs. Most audio inputs will be found on the back of the DVR. They are usually an RCA input. Some DVR’s will allow you to record one, two or 4 channels. The higher end DVRs will allow you to record up to 16 channel of audio. Also, check to be sure that the audio can be streamed over the internet, not just be recorded if you wish to listen to the audio when viewing your cameras remotely.
The first method I recommend for connecting a microphone is with a simple plug and play cable. These are prefabricated cables and are usually available in various lengths up to around 150′ft. They are typically inexpensive. If you wish, you can get plug and play cables that carry the video, power and audio all at once. If you do this, remember that you will need a Y power splitter to split the single power connector to power both the camera and the microphone. This would allow you to run a single cable for your camera and microphone. If you choose to run the cameras separately with maybe RG6 or RG59, then you can use a normal plug and play that has video and power for the microphone. One end of the cable will plug into the microphone audio output using a BNC to RCA connector and into the power input, the other end will plug into the back of the DVR (again using a BNC to RCA connector) and into your power box (using a flying power lead) or into a single power supply.
The second option is to use CAT5. This is especially convenient if you have existing CAT5 installed for your security cameras and you decided to install microphones. You can use a video balun on each end of the cable. I recommend a balun that has power, video and audio in one. Then you can plug the cat5 cable the same way you would have connected the plug and play cable.
The better microphones are very small, easy to conceal and very powerful. You can install the microphone in or near a camera or housing, or even keep it behind the wall in many cases. Once everything is connected, it is usually just a matter of setting the configurations in the DVR.
Tags: CCTV, DVR, microphone, record audio, spy
