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Horizon

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Everything posted by Horizon

  1. Horizon

    Help with type of Coax to use

    Hi the toss. I see the problem here. When I say "RG6" you hear "cable TV coax". The example you've given is CATV coax. This is likely (99% likely) copper-clad-steel, as it is heavily cost-optimised for high frequency use. As you are saying, and which I have agreed with in many previous posts, copper-clad-steel (sometimes known as CATV or digital TV cable) is not suitable for use with low frequency CCTV. I don't see why we're arguing about this point. I agree with your point on shielding, and this site http://www.bluejeanscable.com/articles/shielding.htm gives a good description and comparison between shielding types. Although they don't mention the cable part numbers that were used (which is sloppy, and makes it hard to verify the results), they do claim that quad is half as effective as 95% copper braid and foil. The main cause for concern with copper-clad-steel is the high losses at low frequency. With composite video (analog CCTV), the vertical sync at 50Hz is most susceptable, but the horizontal sync at 15.625kHz will also be corrupted. If you don't have clean sync signals, you will not have a good picture - it will be torn and distorted. I think this is more important than the sheilding, although the quad shield on CATV coax will definitely not help preventing the distorted and attenuated syncs from being swamped with noise. What I disagree with is the claim that all RG6 is unsuitable. There is plenty of solid (or full) copper cored RG6 coax available. I'm moderately familiar with Belden, so here's a link to some: http://docs-asia.electrocomponents.com/webdocs/06de/0900766b806de548.pdf It's designed for CCTV, and it meets the RG6 requirements. Solid copper core, 95% braid and foil. Then I'll move onto tomcctv's claim that HD-SDI can only run on RG59. Again, there is RG6, RG11, and even RG179 that is rated to the full 3GHz. There are plenty of manufacturers that make coax with different grades and quality. Sticking with Belden ('cause I'm lazy), we have a list of distances versus data rates here: http://www.belden.com/docs/upload/Recommended_Transmission_Distance_at_Serial_Digital_Data_Rates.pdf RG179 = 179DT, RG59 = 1855A, RG6 = 1695A, RG11 = 7731A are some examples. This is for professional HD-SDI used in TV studios and movie theatres. I'm not sure what (if any) trade offs have been made for CCTV use. Hopefully none! So now it's clear that TGMcCallie wants to upgrade to HD-SDI, I would highly recommend that he choses his coax carefully, so that it will support the HD-SDI cameras that he wants to install. Personally, I'd go with an IP based system, but that's just my opinion, and everyone is entitled to there own choice. I also recomment that TGMcCallie follows tommcctv's advice and also runs CAT5 cable for power. CAT5 is relatively cheap, and in my opinion (again!) you'd be a bit crazy not to run it. The cables I've used in my examples are all from Belden, as this manufacturer is used a lot in the industry that I'm involved with (which is not CCTV related, and I definitely don't work for or with Belden ). There are plenty of other manufacturers out there that make similar good quality cables. Please don't buy the cheapest generic junk cable that you can find!
  2. Horizon

    Help with type of Coax to use

    Hi, unfortunately abc cables is inaccessable tonight. They're no even responding to ping. Okay, I really am curious as to what the problem is with RG6, and I'd like to know what I'm missing. We are talking about the standard copper RG6 (copper inner conductor, copper braid with 95% or so coverage), and not the copper-clad-steel (CCS) stuff that is used for CATV (cable access TV) or MATV (master antenna TV) systems. CCS coax generally has dual, triple, or quad braids to prevent RF leakage, and to keep the FCC or other spectrum management agencies off the CATV company's back. The copper cladding suits CATV/MATV, because they are running up in the hundreds of MHz, with no low frequency content. I see that you can also get RG59 CCS coax, with siamese power leads. It's claimed to be no different to full copper (yeah right). Some of the stuff even has a copper clad steel braid. Yay. Google "copper clad steel rg59" and take a look at all those horrible hits. Well, it might be okay for short runs, and there may be a way to compensate for the low frequency loss, but I'll stick to full copper (or twisted-pair!). I should be able to locate some links tomorrow - it's getting a bit late tonight. So in summary; copper good, CCS bad. If in doubt, use a magnet! Cheers
  3. Horizon

    Help with type of Coax to use

    Hi Tom. If you are thinking of upgrading to 1080p, then you will eventually want network or IP cameras. You should consider using twisted-pair (CAT5, CAT5E, or CAT6) cable instead. If you want to start out with analog/composite video cameras, then as Numb-nuts has mentioned, you can use twisted-pair with analog cameras through the use of baluns. You can also feed power down the same cable with the video. The cable's cheap, and works great, although the baluns can get pricey, as you need one at each end. Copper RG59 or RG6 is fine for analog CCTV, although twisted-pair provides an upgrade path to IP cameras. Copper clad steel RG59 or RG6 is terrible. It won't work! For more info: http://www.pacificcabling.com/Information/Information_other/CCTV_cable_choice.htm
  4. Horizon

    Help with type of Coax to use

    Hi TGMcCallie You can use either solid copper RG59 or solid copper RG6. Solid copper is needed for the low frequencies used with CCTV. RG6 is better for long distances, as it has less loss. If your distances are less than 200 meters, then RG59 will be best, as it is slightly cheaper. Stay away from the copper coated steel, as this is only for satelite or cable TV use, which operate at much higher frequencies. The copper coated steel cable trashes the low frequency CCTV signals. Just because it works with higher frequencies, doesn't mean that it is a superior grade cable.
  5. That's interesting, becausing looking at the picture, I'd swear that card does 16 channels. I'd b a little suspicious of the description Ubuntu is giving you.
  6. Horizon

    rs-485 issues

    Hi incentive. Do you have the 120 ohm termination resistor installed at the last camera? Also, does the cable go from the DVR to your four encoders, then to your other cameras, stopping (terminating!) at the last camera? It definitely isn't looped back to the DVR; it hasn't been run in a ring?
  7. Good sleuthing yu130960! Yes, there'll be a factory selling those cards to many resellers, who integrate the card into their security products. It's why you see the same card being sold under lots of different names. If you decide to sell it, the "BLUECHERRY PV-981 – 16 PORT VIDEO CAPTURE CARD (120FPS) – (PCI-E VERSION)" is probably the best description to use.
  8. Hi Faisal You could try this link for the XP4/16/32 card: http://www.y3k.com/downloads/software/PCDVR%20Server%20Client%20and%20Drivers%202009.zip If that software doesn't work, they have other software on their support pages: http://www.y3k.com/article/68/downloads-software-firmware-models-a-m http://www.y3k.com/article/81/downloads-software-firmware-models-n-z It looks like a good company - they have tons of manuals and softeware available.
  9. Hi there yu130960. Dunno what the card model is, but you can probably find some generic drivers if you want to use it - the BT878 is very common. Otherwise you could sell them off via ebay.
  10. xrblazer29, you're probably after a generic driver for a 16 channel capture card. The part you need drivers for are the BT878 capture chips. The PLX chip is a PCI to PCI bridge - Windows should take care of it automatically. Yeah, the '878 is an old chip now, and it's getting harder and harder to find a reliable computer with PCI slots to suit it.
  11. Yep, that's a "howell tempest vc878b-q". It's one of the few capture cards that I've seen a manufacture put their name to. I don't know about Windows, although there should be something that works with it, such as Blue Iris. I've mostly played with Ubuntu, and this card is supported by Zoneminder: http://www.zoneminder.com/wiki/index.php/Howell-Tempest_VC_878B-Q Note the warning: "Because each 878a chip is being used to drive 4 inputs, the maximum FPS per input is lower than if there was a 878a chip for each input." This means that it will support one camera per BT878 chip at 25 frames per second, 2 cameras at 7fps, 4 at 1fps
  12. Hi exe. That's the Philips SAA7130HL video capture chip. I've used a four chip capture card, which went fine (using one camera per chip), although I've since moved to cards that use eight Techwell chips. The Philips drivers should be fairly common for Windows. I was using this card with Zoneminder under Ubuntu (Linux), using the built-in Ubuntu driver.
  13. Horizon

    Shoddy Wiring Job

    What a rat's nest! I hate to think what's at the other end of that CAT5. Sharing a CAT5 between two cameras is fine - shouldn't be a problem, but does make neat wiring jobs more challenging. I'd suggest a Krone punch-down block http://en.wikipedia.org/wiki/KRONE_LSA-PLUS, or one of their many clones/imitators. This would work great, provided that the CAT5 cable has solid core conductors (stranded conductors can be unreliable in punch-down blocks). Krone has the advantage of allowing the wires to be secured and strain relieved, and allows the video and power circuits to be neatly split off. One of the problems with that rat's nest is that if the CAT5 cable is moved about too much, the conductors can get metal fatigue and break. And the insulation tape will fall off eventually. There should aready be 24 bauns (one for each camera) plugged into the back of your DVR. Here's some stuff about baluns (random link): http://muxlab.com/wp-content/uploads/2012/10/CCTV-Balun-Application-Guide.pdf There will also be a balun at each camera, unless the camera has the balun built in. Remember that baluns are "reverse polarity sensitive". If you get the wiring crossed over, there will be no video. No lasting damage - just no video.
  14. Hi pilotg2. None of those ebay auction descriptions match the photos! Download the instructions, and compare what's written on the (blue) relays with the ratings claimed in the auctions. I'd go with the first choice http://www.ebay.co.uk/itm/1-Channel-AC-DC-12V-RF-Wireless-Remote-Control-Switch-Receiver-Transmitter-1-CH-/171247862697?pt=UK_Gadgets&var=&hash=item27df2b03a9 and use the "B,C=normally closed" relay contacts. The relay is only rated to switch 250VAC/30VDC. Ideally you'd use a relay with 50 or 60VDC contacts, but in practise you'll be fine switching the 48VDC POE because the Hik camera draws so little current. The relay in http://www.ebay.co.uk/itm/1-Channel-AC-220-240V-DC-Wireless-Remote-Control-Switch-Receiver-Transmitter-1CH-/171188670543?pt=UK_Gadgets&var=&hash=item27dba3d04f is not rated for 250VDC, it's only good to 30VDC. The ebay description is wrong. Don't use this one, as you also need a relay that has "normally closed" contacts. And, being mains powered, it's riskier to experiment with, and a nuisance to mount safely into a box.
  15. Horizon

    How long can I make the RG6 cable?

    Sadly it's no joke However, looking at the number and size of the LEDs, 500mA would be more realistic. That way you'd have 3 watts for the camera, and 1 watt for each LED. Yet if they've mucked up the current consumption (twice!), I'd be worried about other parts of the description. Throwing extra zeroes around the place like that - sheesh!
  16. Horizon

    How long can I make the RG6 cable?

    Hi Scampo. Just a heads-up with that camera: According to the description, it will consume 5 amps with the IR light on, so you'll need a thick power cable to connect the power supply to the camera. You might have to power it locally (from a nearby power outlet) rather than running a cable back to the DVR. Also, they don't include the power supply, which will add to the cost.
  17. Horizon

    Wired the camera to mains

    Hi Survtech.Yep, I think we're generally in agreement. Have you seen many 24VAC cameras being made that are not able to work with 12VDC? Modern ones, that is, not like the ancient black &white 24V Burles I have I'm curious to know, so I can find out why and how they've done it. Yeah, 30VAC is getting up there a bit. I'd hope that there was a nice long cable to the camera to provide some voltage drop. If the camera has a switch-mode power supply, it shouldn't run any hotter at the higher voltage. Linear power supplies would, but no manufacturer would one at that voltage - the losses would be too high (and as you say, it would run HOT). As for the comment about sophisticated voltage regulators, they pretty much all are sophisticated now. Surprisingly, they're cheaper to make than the simpler linear designs.
  18. Hi there jmk. I like your approach here, but I think the loss through the cable will defeat you The 24VAC to 12VDC converter will easily tolerate your 36V supply ( 24 x sqrt[(2] = 34 volts). The converter internally transforms AC to DC, so since it works on 24VAC, it must work on 34VDC. According to an online calculator, a single 800 foot length 24awg has 22ohms of resistance, so double the resistance to include the return path, and then halve it because you are using two pairs. Sketching about on the back of an envelope, it looks like more than a quarter of your power will be lost through the cable, and even 36V won't be high enough. It depends a lot on how low an input voltage that converter will work with. You might be okay if the length is nearer to 600 ft or less. If it was me, I'd use a higher voltage - 60 volts is the maximum you can use without needing an electrician to do the wiring (or at least, it is over here), so I'd use something between 50 and 60V, and a different converter to step it back down to 12V. Choose one that can deliver at least 30 watts to the camera. Or power it locally at the pole if that's possible. The PTZ will only draw 20 watts when it moving. When idle, it should be more like 5 watts or so, unless it has infrared LEDs or a heater. So your power bill shouldn't get too high BTW, that open frame power supply (the 36V Hengfu) must be put into a box before you start experimenting with it. Stray wires are magically attracted to mains terminals, then you get zapped!
  19. Horizon

    Wired the camera to mains

    Some cameras can tolerate large voltage drops: From a theoretical point of view, a camera designed to work with both 12VDC and 24VAC will also work from 12VDC to 34VDC, and 8.5VAC to 24VAC. If the camera has a minimum working voltage of 10VDC, then when you are using it with 24VAC, you could have up to 17VAC headroom, meaning that it can tolerate a lot of voltage drop. This compares against only 2 volts of headroom if you were supplying it with 12VDC. In theory (of course), and making a few minor assumptions And when you double the voltage, you halve the current (for the same amount of power), so you will get twice the distance for the same amount of voltage drop. It makes this kind of camera very easy to work with. And if it has an isolated switch mode power supply it gets even better, because that breaks the ground loop. Bonus! To the OP of this elderly thread, if the power board was replaced, the camera might have been salvaged. It's unlikely that the mains would get through the power supply to the low voltage camera electronics. Youtube linky (a bit of a bang) Note - turn down the volume, it starts with a bang and then gets louder.
  20. You could hide them in the base of your mailbox. Build a platform that the box sits on, and hide them in that. If you want to be sneaky, put them in something that belongs there. I've been toying with this idea myself, so I can monitor my front door and yard.
  21. Horizon

    How long can I make the RG6 cable?

    RG6 is great, so long as it doesn't use a copper covered steel inner with aluminium braid. The same goes for RG59. Pure copper inner and braid (the braid with 95% coverage) is best for both RG59 and 6. RG6 will give you more range. The type of connector you use often depends on the tools you have on hand Here's a link for more info: http://www.pacificcabling.com/Information/Information_other/CCTV_cable_choice.htm
  22. akv, you could try a Watec-902h. These are a fairly old monochrome camera, that can do 0.0003 lux with a F1.4 lens. This camera doesn't use sense-up, as it doesn't support that feature. It has a resolution of 570 lines which is probably as good as you'll get from an analog camera. It is also physically small, which would help with mounting it in the same enclosure as the IP camera, but you'll still need something to encode it into an IP format, unless you are going to use coax or baluns. You'll need to use an auto-iris lens to protect the camera from bright sunlight. In this case, look for a later model Watec, as the earlier ones used a non-standard pinout for the auto-iris connector. I do agree with thewireguys, in that you should check that you need this extreme sensitivity.
  23. Horizon

    Help!!!! 8CH/RJ45/BNC switcher???

    Dunno whether these cameras will do Power Over Ethernet (POE). SunnyDaZe, do the camera instructions mention POE or 802.3af ? I'm guessing that these cameras can only be powered from the plug packs, so you'd be able to use a normal Ethernet switch.
  24. Horizon

    Help!!!! 8CH/RJ45/BNC switcher???

    Hi SunnyDaZe. Those are IP (Internet Protocol) cameras. They talk to the Network DVR (your black box) across Ethernet. That is a Network DVR isn't it? At a guess you need a network switch between the cameras and the DVR, unless that is built into the front of the DVR. The composite video / BNC / yellow plug is for when you set up the cameras. Afterwards it isn't used. Well, it can be used, but the picture is nowhere as clear as what you'll get over Ethernet.
  25. Hi Conor. The PLX PCI6140 is a PCI to PCI bridge. It interfaces the video capture chips to the computer's PCI bus. You will have other slightly smaller chips on the card, probably four of them. These are the ones that do the video capture. What are their numbers? Yeah, TV quality (and low definition TV at that) is what you'll get from this composite video capture card. IP cameras are better, but composite is still adequate for many tasks.
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