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survtech

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Everything posted by survtech

  1. survtech

    Cable Length and Correct Cable

    Did the electrician run the 110VAC in the same conduit as the video? That will cause you problems. Video cables should be separated from power by at least one foot per 100VAC. Also, what is the part number of the Belden video cable? It doesn't matter if the cable center conductor is tinned, as long as it is solid copper core. You can test by bending the center conductor. If it bends relatively easily, it is copper. If it is very hard to bend, it is probably copper clad steel, which is unsuitable for CCTV - especially in runs longer than 100ft. You can also test with a small magnet. The shield is as important as the center conductor. It has to have a low resistance, just like the center conductor. Aluminum foil is not a problem, as long as there is sufficient copper (not steel) drain wire running with it - tinned or not. Every splice is also a potential source of problems. It is best to avoid them wherever possible. If you do have to splice coax cables, "F" connectors are not suitable for CCTV splicing. Use high quality BNC connectors with gold-plated center pins. I've seen nickel-plated center pins corrode and cause poor connections. Compression-type BNC connectors are very good. If there is a potential for moisture getting into the splice (underground or outside), use compression connectors with suitable splice boots packed with silicon dielectric compound (available at auto parts stores).
  2. survtech

    Arm jdvr16320cd dvr 16 channel

    I installed one in a local charity and set the frame rate and resolution for all channels simultaneously through the simplified process described in the manual. But I recall that there was another way to set each channel individually. I don't have the manual so I can't describe the method, though. I liked that it has two ways to burn a CD: a simple key sequence entered during searches will write a file of an individual camera and copy the viewer onto the CD and the on-screen menu allows more advanced burning with multiple cameras and other options. The downside of all ARM products, including this one, is that the manuals are confusing and not well written. And their website leaves much to be desired.
  3. survtech

    8 min gap in recording

    Does Richard Nixon's former secretary work there? Seriously, how is the camera powered? I've seen many situations where camera power was disconnected accidentally by someone wanting to use the outlet or checking breakers or a myriad of other reasons. If all else fails, check and/or replace the DVR's hard drive.
  4. survtech

    My Birthday present.

    That's a great idea.
  5. survtech

    Mosquito teenager deterrent

    That would have driven me nuts well into my twenties. I was able to hear 22kHz in my late teens and when I was 25 I worked in a store that had an ultrasonic sensor in its alarm system. That was supposedly 19kHz. It gave me headaches. This product's specs say that it is above 16kHz. That would have been well into my hearing range.
  6. survtech

    24V power supply question

    You're safe if the power supply is an actual transformer, which does isolate the ground. Not so if it is not.
  7. survtech

    24V power supply question

    You don't need regulated 24VAC power. In fact, most 24VAC camera power supplies actually put out 25-28 volts.
  8. survtech

    1/2' CS lens on a 1/3' CS camera ?

    You will need to get a "C" to "CS" adaptor (a 5mm spacer) if it is a "C" type lens. Otherwise, no problems. The problems come when you try to put a 1/3" lens on a 1/2" camera (or any "smaller" lens on a "larger' camera). That will cause tunnelvision.
  9. Having extra cable length is not a bad thing, it allows you to restructure the camera list if the need arises. But it should have been done neatly, which obviously, it was not. If you have any other problems with PTZ control, you might want to contact Sennetech at http://www.sennetech.net/. They really understand control codes and make some excellent products. Many manufacturers recommend them. The 9760 only outputs Pelco "P" protocol and can't run two different baud rates on the same port. You will have to set all PTZ's to "P" and 2400 baud or put the 4800 baud ones on a separate control line. You could use Sennetech's P to D and D to P translator (http://www.sennetech.net/manuals_pdf/SC%2050/SC-50-Pelco-422.PDF), but that is not the elegant way to do it. One trick we use is to put Kalatel KTD-83 Data Signal Distributors out in the casino and a run single line back to the matrix for each port. You can daisy chain the PTZ's from there - as many as you want per line (up to 32 max per port) if you turn off termination on all but the last one in the chain. KTD-83's come in two configurations - 1 in by 5 buffered outputs and 1 in by 16 buffered outputs. The specs for the 5 output unit are here: http://www.gesecurity.com/portal/site/GESecurity/menuitem.f76d98ccce4cabed5efa421766030730?selectedID=6633&seriesyn=true&seriesID=. The 16 output unit's specs are here: http://www.gesecurity.com/portal/site/GESecurity/menuitem.f76d98ccce4cabed5efa421766030730?selectedID=6634&seriesyn=true&seriesID=. Although they call them RS-422 data distributors, they will also work fine with RS-485 data. In fact, based on Sennetch's advice, we daisy chain up to 3 PTZ's per output without turning off the termination on any of them. Although this makes the load 33 ohms instead of 100, the CDU-T's and KTD-83's can handle much lower impedances without problems. This allows us to run 15 PTZ's per KTD-83.
  10. survtech

    Elevator surveillance

    The only cables allowed for elevators are the "traveller cables". If there are no spares in the traveller, the only options are for the elevator manufacturer to add a second traveller or wireless. Unfortunately, adding a traveller can be expensive. It is not uncommon for the cost to be in excess of $10k. You may need two sets of spares - one for the video and one for power. You would then use baluns to convert the twisted-pair video. Many, but not all, traveller cables include a coax for video and 18 guage twisted-pairs. Sometimes the pairs are shielded; sometimes not. You may have an option to power the camera from an outlet located on the roof of the elevator or you may have to run power in a pair in the traveller. If you use roof power, keep in mind that it can be shut off by a switch in many elevators. Wireless doesn't work very well because standing waves alternately add to and cancel out the signal as the elevator moves. You'll have to get the elevator info from the building owners and probably contact the manufacturer's rep to find out what spares are available.
  11. survtech

    New cctv

    Particularly check out the Channel Plus website. They have designs for and complete kits that may do what you want.
  12. survtech

    New cctv

    There are a number of manufacturers of RF Modulators, notch filters and combiners that can be used to insert video and audio signals on existing cable. Check out these: http://www.channelplus.com/ http://www.blondertongue.com/ http://www.picomacom.com/ http://www.starkelectronic.com/akrfdm3.htm
  13. survtech

    Wire question

    You added an "e". The correct link is http://www.scpcat5e.com/.
  14. The "English" link on your website is in Chinese. http://www.tsingvision.com/en/index.asp: "无法找到该页 您正在搜索的页面可能已经删除、更名或暂时不可用。 -------------------------------------------------------------------------------- 请尝试以下操作: 确保浏览器的地址栏中显示的网站地址的拼写和格式正确无误。 如果通过单击链接而到达了该网页,请与网站管理员联系,通知他们该链接的格式不正确。 单击后退按钮尝试另一个链接。 HTTP 错误 404 - 文件或目录未找到。 Internet 信息服务 (IIS) -------------------------------------------------------------------------------- 技术信息(为技术支持人员提供) 转到 Microsoft 产品支持服务并搜索包括“HTTPâ€
  15. survtech

    Extremly bright image

    I wouldn't worry too much about the circuit board mod. Pretty much all manufacturers do that. It is just a simple production change that isn't incorporated into circuit board production yet.
  16. Most CCTV distributors have them. We use SSI/Northern Video Systems and they have them.
  17. survtech

    ARM Electronics Catalog

    We've purchased some ARM products from SSI. They are mixed in quality. Their quads are OK and their cameras are decent. We installed their C540MD2VAI outdoor bullets at a local charity and, except for somewhat cheesy mounts, they are pretty good. We also installed a DVR16320CD240 and it is relatively easy to set up and works pretty good.
  18. survtech

    Any tricks to getting a nice focus?

    One trick is to get the zoom and focus close to optimum; then tighten the lock screw enough to still allow movement but have some resistance; then finish the zoom or focus. On some varifocal lenses, zoom is less critical than focus so we adjust them both for the appropriate field of view and nearly the best focus, lock the focus ring and complete the focus adjustment with the zoom. The neutral density filter is a must with auto-iris lenses and in changing lighting environments. One trick there is to get #5 or #6 welding glass from a welding supply store. It tends to shade the color slightly but is cheaper than filters and works nearly as well.
  19. survtech

    Non-PTZ vs. PTZ

    In casinos, we usually cover every square inch with fixed cameras and use PTZs strategically placed to allow the operators to zoom in on problems. The problems with PTZs are that they require an operator to control and can miss things if you rely on only them to cover an area and they are aimed at another area by an operator.
  20. They are available at many stores and distributors: Radio Shack - http://www.radioshack.com/product/index.jsp?productId=2103065&cp=&pg=2&sr=1&origkw=video+splitter&kw=video+splitter&parentPage=search ARM Electronics (many places) - [edit by mod - link removed] Do a web search for video distribution amp(lifier).
  21. You can't just split video signals. You have to use a Distribution Amp.
  22. Actually, that would be 37.5 ohms total. Two equal value resistors in parallel equals 1/2 the resistance, not double.
  23. Check the termination settings on the DVR and the Quad. When looping video to another device, the last device in a chain should be terminated and the rest should be unterminated.
  24. survtech

    Vertical White Line

    A thin vertical white line is not the symptom of a bad picture tube. It is caused by a problem in the horizontal deflection circuit. Either the yoke, or most likely a bad transistor or other part there. Do not attempt to replace the CRT unless you know what you are doing.
  25. Pelco does have classes. They call it the "Video Security Institute". Find it here: http://www.pelco.com/support/vsi/. You can also find traing books and tapes/dvds here: http://www.ltctrainingcntr.com/. Or do a web search for "CCTV training".
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