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survtech

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Everything posted by survtech

  1. Here's a nice 24VAC Wire Distance Chart, courtesy of Pelco: ftp://www.pelco.com/ServiceBulletinsTechTips/TechTips/5973024.PDF
  2. survtech

    Who sells Honeywell CCTV Products?

    Surveillance Systems Integration (SSI), Northern Video Systems' integrator partner. http://www.ssicctv.com/
  3. survtech

    Ideal framerate

    The most efficient codec right now is h.264. It has the best quality with the smallest file sizes.
  4. You'd have to go to something like a mesh wireless system and IP cameras. Mesh systems can transmit up to 50Mb/sec or so. The number of cameras, their bit rate and frame rate would determine your limits. In any case, fiber would probably be your best bet.
  5. You'd have to go to something like a mesh wireless system and IP cameras. Mesh systems can transmit up to 50Mb/sec or so. The number of cameras, their bit rate and frame rate would determine your limits. In any case, fiber would probably be your best bet.
  6. For that distance, your only options are fiber and wireless. Twisted-pair and coax just won't cut it. Even RG-11 coax is only suitable for maybe 2000 ft. (600m). The nice thing about fiber is that you won't need that many strands. And power supplies will have to be local. There would be far too much voltage drop across any power cable.
  7. survtech

    Video Baluns and Cat 5

    The ones we use typically cost $25 to $30 each. The thing about baluns is that, despite the claims by some manufacturers, there really isn't much difference in the design or the costs of the parts. Basically, a balun is probably $2 to $3 worth of parts. See the schematic and diagram below: A couple of connectors, a circuit board, a small transformer and a plastic case don't add up to much.
  8. survtech

    Video Baluns and Cat 5

    Yes, we have a DA at the end of the chain for all cameras; coax or TP. But transmission is TP with passive baluns at both ends for maybe 1/3 of the cameras - the rest are coax. Camera - balun - CAT-5 - balun - MDA - Matrix ------------------------------------------------- DVR Encoder ------------------------------------------------- Other (occasionally)
  9. survtech

    Video Baluns and Cat 5

    rory, I don't know in what situations or with what cameras and equipment you have had bad luck with baluns but I manage the techs at a major casino and we pretty much switched to twisted-pair years ago. We have used passive baluns almost exclusively for new camera installs since then and have encountered almost no problems with good quality CAT-5 up to 500 ft. We've used a number of manufacturers' baluns and noticed little or no difference in the signal between them. We tried NVT, Vigitron, GVI and VideoEase. In our tests, there was no discernible difference between brands, despite NVT's claim to superiority (at, of course, far higher cost). We have used active receivers for runs up to 1,500 ft. and there the results have been somewhat less than stellar. We are in the process of replacing a Vigitron 16-channel active receiver with Pelco TW3004AR units because the Vigitron unit adds too much noise to the signal. In our case, we are very proud of the quality of images obtained on our cameras, especially on table games. We have two of the same make and model of fixed cameras next to each other, aimed at adjacent tables - one with coax and one with twisted-pair and there is no difference in the picture between the two. One difference may be with the cameras. We have used Pelco CCC1300h series almost exclusively on table games until recently (CCC1300h2, CCC1370h2 and CCC1380h6). We now use them and some Ganz ZCD3000 series mini-domes with built-in NVT baluns for new installs. We also use Ikegami cameras for low-light, less critical areas because the Pelcos have poor AGC quality (muddy pictures). Another possible difference is that every input to our matrix and DVR encoders is buffered by a Pelco CM9760-MDA. Perhaps if we didn't use the MDA's our results would be different. In fact, there are some distinct advantages to twisted-pair. We pulled 500,000 ft. of RG-59 during the casino's initial expansion - 10 to 20 cables at a time. That was very difficult and time consuming. With twisted-pair, we can pull 25-pair anywhere with relative ease and co-locate the punch-downs near the camera power supplies; making the final pulls to the cameras very easy. Also, we have started switching over to the West Penn siamese (1x18/2 + 2x24/2 TP) cable for the final runs to the cameras which saves even more time.
  10. survtech

    Video Baluns and Cat 5

    Active baluns can be at either end of the line - active receivers or active transmitters. Typically, manufacturers recommend passive-passive for runs to 1000 ft, active-passive (active at either end) to 2000 ft. and active-active (at both ends) up to 4000 ft. Active means powered. They also need access to power, either 110VAC, 24VAC or 12VDC from a power supply. For runs that short, I have not found any significant difference between active and passive baluns. In fact, some active baluns may not be able to "turn down" their compensation for that short a run and may "over-EQ" the signal. Plus, active circuitry tends to add some noise.
  11. survtech

    Video Baluns and Cat 5

    300 ft. is no problem for passive baluns. Hookup is very simple - place a balun at each end keeping the (+) and (-) on the same colors of the pair. You can splice if needed using "beans" or whatever you have for small guage wire. Keep twists in the wire pair as much as possible.
  12. You often must install proprietary codecs on a PC to play video clips generated by many DVRs. That's because Microsoft can't/doesn't include codecs for ever possible media format with Windows. Also, for anyone wanting a full-featured media player that is both simple and free, try VLC Media Player available here: http://www.videolan.org/vlc/.
  13. survtech

    Sata Raid 0 with WD Raptor

    With XP Pro or above, you can just load your O/S and data on one drive, go to Windows Disk Management, right click on the primary drive, and then select mirror. It's a very simple process.
  14. survtech

    Major Players in the CCTV Industry

    Huh? What am I selling and to whom?
  15. survtech

    Major Players in the CCTV Industry

    They're not alone. Many "manufacturers" do the same. At least I posted a list.
  16. survtech

    Major Players in the CCTV Industry

    American Dynamics ARM Electronics Bosch Computar/Ganz (CBC America) CSI/Speco Elmo Everfocus GE Interlogix Honeywell/Ultrak Ikegami JVC KTL Panasonic Pelco Philips Pro-Video Samsung Sanyo Sony Toshiba Watec And many other smaller manufacturers; especially based in asia (China, Taiwan, Korea, Japan and Malaysia).
  17. survtech

    Need advice - repeated targeted burglaries

    There is a simple solution to her problem. Change the locks and lock all doors and windows. Then it is breaking and entering!
  18. Well, it's worth a try. I would lay the approximate length of wire that you plan to use on the ground and hook it up temporarily first before running it permanently. That way you will see if it causes any problems with the video.
  19. survtech

    Crimp on or Twist on?

    Here is a link to how to install one manufacturer's compression fittings: http://www.arrisistore.com/digicon/Digicon-BNC-Connector-Installation-Guide.pdf
  20. Sheilded audio cable? No, I wouldn't recommend that. Although this is not a critical application, you still need to use a cable with the correct impedance (75 ohms for coax). Audio cable will probably give ghosting and other problems. Sorry, I didn't mean that you could use anything, you just don't need RG-6. By the way, to bridge the gap, have you thought about stringing the cable overhead? I've used antenna guy wire between two buildings and hung the transmission cable from that with loose wire ties or good electrical tape before.
  21. survtech

    Crimp on or Twist on?

    For coax, especially mini-coax, we have been switching to compression fittings as we run out of 3 and 4 piece crimps. There is no comparison for strength of connection and they are even easier to assemble than the standard fittings.
  22. Don't listen to that, 99% of RG6 is aluminum and NOT DESIREABLE for CCTV use. RG6 is designed for higher frequency digital signals used by cable companies. didn't know that.. about 80% of the coax running around the plant where i work is rg6... Not really true. Yes, a lot of RG-6 is for TV/CATV RF use but every manufacturer makes 100% copper center w/95% copper braid shield (CCTV quality) RG-6. Examples include West Penn 806 series (regular, plenum, direct burial, flooded burial and Aquaseal), Belden 533945 and many others. However, that misses the point. For runs of 100 ft. or less, darned near anything will work - twisted-pair (Cat-anything), mini-coax, RG-59, even CATV cable with clad center and aluminum jacket. This is especially true for lower resolution cameras (ie. less than 400 lines). If you use a cheap wireless system for the last 20 ft., that will be the limiting factor for image quality, not the cable.
  23. survtech

    Crimp on or Twist on?

    Actually the techs that used them are no longer with the company. They won't be missed .
  24. survtech

    Crimp on or Twist on?

    To all of you who use twist-on connectors, I will quote from someone who is a recognized industry expert - Charlie Pierce of LTC Training Center: "Although the Screw-on BNC connectors appear to save you time in the field, they have too many factors against them to make them a true cost saving factor. 1. Screw-on connectors can and do vibrate loose, causing for sporadic video signal problems. 2. Screw-on connectors are not considered moisture tight and in actuality suck up moisture through the threaded base of the connector causing corrosion of the coaxial cable. 3. Most cases of connector problems that I have seen, that involve the Screw-on connectors are caused by improper installation of the connector and/or the use of a cheap connector. 4. These connectors cannot be used in any circumstance where; the cable may be in motion (pole to pole or pan/tilt installations); outside (to many humidity problems); or where the connector may be put on and taken off a piece of equipment often (field patch cords). In the end, many manufacturers of cameras systems are starting to label the Screw-on BNC as an illegal connector due to the extensive problems found in the field. My best advise is that if yours is a long term company, stick to the three piece crimp on BNC connectors. At the end of the day, a good technician can install a three piece crimp on BNC connector in the same amount of or less time than a Screw-on connector. " http://www.ltctrainingcntr.com/ In my experience, I found his comments to be true. When I was first hired where I work now, the techs used screw-on connectors often. I couldn't believe how bad the connections were. As I was going around checking the matrix for problems, I was having jumper cables literally fall out of their connectors. They were causing bad signals everywhere. In actuality, we are not using even crimp-on connectors much anymore and we never use twist-ons. More and more we are converting to compression connectors. IMO they are superior in every way to both of the other types.
  25. survtech

    Crimp on or Twist on?

    NEVER, EVER use twist-on connectors, period! They don't last; they pull loose; they make poor contact and they are generally pieces of crap suitable only for amateurs.
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