A. Mic levels are very weak, generally around -60dBm. Output impedance will depend on whether or not the mic has a transformer ( balanced output ). If not the mic will be "high impedance" ( hi Z ) and must be connected to the right kind of input. The cable must also be very short to avoid noise issues. If the mic has a transformer, it will be "low impedance" and should have a balanced input mic preamp. The cable can then be several hundred feet long. Balanced output, low impedance mics are usually more expensive and generally found in pro applications. Balanced outputs must have three pin connectors. Line levels are much stronger, consumer -10dBm to professional 4dBm. Line level signals must be shielded.
Q. What's the difference between "plenum" and ordinary cable ? Our engineer specified "plenum" , it makes quite a difference to our pre wiring costs. L.P. AR
A. Plenum cable can be run inside air ducts ( plenums ) and has more stringent health and safety requirements. The quality of the video product is the same.
Q. One of our IT guys says we should be installing UTP throughout our building at the same time as new coax. Why should we install UTP ( what does that mean ) as well as new coaxial? RichardK.
A. UTP means Unshielded Twisted Pair ( cat 5 or 6 ). If a digital network is in your departments future and wiring is difficult it's probably a good idea to pre-wire while you have the ceilings open. However, ensure you get professional advice from an IT expert.
Q. If I buy a camera with great low light level abilities do I still need to concern myself with improving the lighting in the interview room ? D. Collins, NJ
A. Absolutely ! If you try to record video in a poorly lit room and rely on the camera's low light abilities to properly expose the scene you will be very disappointed. In most cases you will want to use "daylight" flourescent tubes and lots of them. Make sure your walls are painted in a flat "off white" paint. We will be providing links to other web pages that will provide you with a more detailed answer.
Q. Do you only sell to the police community? Your web page leaves the impression that "law enforcement" is your company's only concern. JT, Sudbury, Ont
A. We sell our product to government agencies, law firms, banking institutions and many other organizations that have a requirement to record meetings, interviews, complaints, etc onto a media that can be readily copied, stored, transcribed and played on a multitude of devices. Our DVD's can be played on almost all PC's and most newer consumer grade DVD recorder/ players. Policing is where our "team" came from and where our loyalties lie. Most of our sales are to the "Law Enforcement" community.
Q. Do you still sell and service VHS systems? Our department spent a small fortune three years ago to equip our interrogation room with VHS recorders from a local alarm company that has since closed shop. We would like to upgrade, but don't want to replace everything we have just to go to DVD. Roger Burton, Boston, Mass.
A. IRSystems have converted entirely to DVD technology, although we still provide support for our "old" VHS systems we no longer offer them for sale. If you are satisfied with the audio and video product you were getting from your old system it surely can be recorded on our equipment. You will have to provide us with some technical information ( make, model, etc ) of your camera(s) and microphone(s) in the event we have to supply new connectors or possibly a pre-amp.
Q. Why don't you sell less expensive brands of equipment? My department has been using ____________CCTV equipment for years with good results. Peter Sills.
A. We promote PELCO equipment for a number of reasons ( by the way, we don't receive any benefit from PELCO for doing this ). PELCO is a quality American company that manufactures most of it's equipment in the USA. PELCO maintains a high standard in it's manufacturing process and stands behind it's product. PELCO equipment is professional in every way. PELCO is definitely not the cheapest product available, but as far as we are concerned, quality and our wish to buy "at home" does come at a price. We have always promised to sell quality equipment at a fair price. Our DVD recorder is made by DATAVIDEO and it is not manufactured in North America. This piece of equipment is not "cheap" either, but it is without doubt the best DVD recorder available for police use at a price that we can all live with.
