survtech

Mis-spelled word for testicles, as in "Never Mind the Bollocks, Here's the Sex Pistols". But apparently cybernettaxis has a very strange anatomy since he says: The Urban Dictionary defines gahoonas as "The breasts of a women". If he (she?) has breasts between his (her?) legs he (she) must be some kind of alien.

Actually, we use CAT-5 with passive baluns for most cameras up to approximately 1000 ft. For longer runs we use passive transmitters and active receivers. When we use RG-59, we usually use West Penn 815 or 25815 for RG-59 and 825 or 25825 for mini coax (the 25xxx is plenum). For power, you need to know how much power or current your camera needs. If the camera spec lists current draw, multiply it (remember it usually is in mA, which is 1/1000 amp, so 250mA = .25A) times the voltage to get power and plug that and the distance into the calculator here: http://www.vihon.com/Vihon_Calculators/Vihon_Wire_Gage_Calculator/body_vihon_wire_gage_calculator.html Ignore the "VAC" next to "Source Voltage Amplitude ", it works equally well for VDC. Most cameras can tolerate a 10% Allowable Cable Voltage Loss. Many 24VAC cameras can tolerate up to 20%, but that is pushing it. A few 12VDC cameras only allow 5%. Also keep in mind that most 24VAC power supplies actually put out 27-28 volts and some can be adjusted to 29 volts. Some 12VDC power supplies can also be adjusted higher to compensate for longer cable runs but you are best off using 12.0VDC and 24.0VAC in any calculations to allow a bit of headroom.

Decent quality RG-59 cable only can extend as long as 1,000'. This is the norm for this cable and without any arguments. I beg to differ, as does much of the industry. For one thing, it depends on whether the center conductor is 22 gauge or 20 gauge. Both are common. The smaller the gauge number, the larger the diameter of the center conductor and the farther you can run the cable. Pelco: In the average CCTV installation, with cable lengths of less than 750 feet (228 m),RG59/U cable is a good choice. West Penn: The RG-59 has the highest attenuation of the three other types and you can expect to get a distance of about 750 - 1,000 ft. (note: All West Penn RG-59 CCTV cable is 20 gauge) securityideas.com: In the average CCTV installation, with cable lengths of less than 750 feet (228 m), RG59/U cable is a good choice... For short cable runs, use RG59/U with a 22-gauge center conductor, which has a DC resistance of about 16 ohms per 1,000 feet (304 m). For longer runs, the 20-gauge variety which has a DC resistance of approximately 10 ohms per 1,000 feet will work well. Commscope: Cable - Distances (feet) Mini Coax - 350 RG59 Coax - 750 RG6 Coax - 1500 safetysecurityonline.com: While cable manufacturers say you can run RG-59 out to about 750-1,000 feet, we recommend not to run RG-59 more then 600’ from a camera to the DVR, otherwise you may experience signal loss and subsequent picture interference. RG-6 can usually be run at least 300 – 400 feet further than RG-59, but it does cost more. There are many more examples. If you use premium 20 gauge copper/copper RG-59; if the connectors are installed properly and if everything else is proper, you might be able to squeeze 1000 ft. out of RG-59 but I would personally rather err on the side of caution than have to replace the 950 ft of RG-59 I just ran with RG-6 because the picture was screwed up.

I haven't seen a lot of Polls, but there seems to be a number of Brits and Aussies

There are at least 2 different lens sizes for board cameras, M12 x 0.5 and M9 x 0.5. Make certain you get the right size for yours. You can also check Marshall Electronics for board camera lenses. They have a wide range of focal lengths: http://www.mars-cam.com/optical.html

Try reversing the pair on one of the baluns for each bad camera.

You should keep in mind that you will have to connect some type of controller to each PTZ to set it up for aim, zoom and any tours or presets you want. Then, if the power is removed from any of them, they will probably default back to a factory "park" position, so you will have to re-aim them back to where you want them and/or restart the tour.

Well, here we go just for fun measured DC and AC current for CNB dual voltage D2315 camera 12V---.26A ~ 3wt 24V---.13A ~ 3wt not to be mean but... plz call back Nuvico tech support and ask if anybody ever measure current and at the same time ask if anybody remember Ohm's law u might be surprise with answer Bravo!!! Unless they internally drop the voltage from 24V to 12V by dissipating it as heat (I doubt they would use a DC-DC inverter due to cost), the power drawn by the camera should be the same. If the voltage doubles (12V to 24V) the current would be cut in half (500ma to 250ma). Then again, it doesn't hurt to over-rate the power supply.

Well, 500ma is 1/2 amp. Therefore, each output of the power supply should be fused at 1 amp. If you have 16 of those cameras connected to a single power supply, the supply should be rated at 8 amps total plus at least 20% headroom or 10 amps total. You can get a power supply rated higher than that, but no lower.

18/2 is not usually used for PTZ control. It is mostly used for power. For one thing, it would be the wrong impedance for RS-422/485 which typically works best with 100 ohm twisted-pair cable. In my experience, one pair of CAT-5 or CAT-6 works well, as does 22/2 shielded or unshielded. Some PTZ cameras use "up the coax" control, which places the control signal on the same coax as the video. A very few PTZ's still use RS-232 control and that is where 18/2 shielded works best. However, RS-232 control has major distance limits, whereas RS-422/485 can be run up to 4,000 ft.

You might want to double-check the specs with Nuvico. First, there are no regulated 24VAC power supplies that I know of. Second, if the camera draws 500ma at 12VDC, that would be 6VA (approximately the same as 6 watts) (0.5 x 12). If it still draws 500ma at 24VAC, that would be 12VA (approximately the same as 12 watts). So the big question is what happens to the extra 6VA (watts)? It can't just disappear into thin air so something has to dissipate it. While 6 watts doesn't sound like an awful lot when compared to a 100 watt light bulb or a 1,500 watt space heater, it is a lot when it comes to electronic equipment. If that power is not used by the electronics, it has to be dissipated as heat. 6 watts is a lot of heat to dissipate, especially in a camera.

To add to that, I wouldn't recommend connecting a camera that is rated to draw 1000ma to a power supply that is rated at 1.1 amp (1100ma) maximum per channel. That is asking for trouble! Common practice is to never exceed 80% of maximum rating; therefore each channel should be rated at least 1.25 amps (1250ma) and the supply as a whole should be rated at least 1.25 times the total current draw. One question: Few 24VAC cameras are rated in milliamps and relatively few cameras other than PTZ's or IR cameras with built-in IR LED's draw that much power. Most are rated in VA (volt-amps), which is voltage times current. Usually only DC cameras are rated in ma. Are you certain your cameras operate on 24VAC?

DC Iris (or auto-iris, since video iris is basically the same), actually opens and closes an iris in the lens using a motor and an electronic signal from the camera. AES only electronically varies how long the individual pixels are addressed. It works similar to a shutter, but its operation is purely electronic and is not capable of handling as wide a variation in lighting as an auto-iris lens. AES, however, responds much faster to lighting variations than auto-iris.

Mounting the PTZ sideways would make control very difficult; especially if you are trying to follow a moving object or person. One possible solution is the Pelco Spectra IV SE Horizon Series Dome Systems, which can tilt 18 degrees above the horizon. Here is a link to their specs: ftp://ftp.pelco.com/ProductSpecs/Pelco_Spectra_IV_SE_Horizon_Series_Dome_Systems_spec.pdf

Is the cable integral with the camera and has a female bnc and one pair for power? If so, it could be anything. Some manufacturers use RG-174 mini coax or an equivalent; some use audio coax and some just use an 18-gauge pair for video. The type of cable used for very short runs like the stub coming out of a camera has little effect on the picture. The problem is that there is no "standard", so you will have to find out for yourself what kind of cable and/or connector to use.

There might be an internal fuse. That's one of the reasons I dislike 12VDC for cameras. Some manufacturers have "crowbar" protection for reverse polarity, with a diode and fuse; some use a full-wave rectifier bridge so that polarity is not an issue. Unfortunately, many manufacturers cheap out and don't use any form of reverse polarity protection, thus saving approximately 50 cents or less in parts costs.

Don't forget the duct tape for mounting the cameras.

Great pictures. I'm sure you can make a killing selling those cameras to abstract artists. They would also be suitable if you needed to prove someone stole your blue thingy, whatever it is! What line of work is your sister in? I think I saw her webcam on the internet. Oh, and that is not four cameras. That is two cameras; one repeated three times.

Did anyone else notice that his main store is in The Netherlands?

Great. I would like to see your results - especially with multiple (say 4 or more) cameras. You might want to test this capability since USB typically has a 12Mb/s maximum data rate, which can throttle back to 1.5Mb/s. If that doesn't work, you could also look into firewire cameras. IEEE1394/Firewire supports data rates to 1600Mb/sec so it could handle a lot more cameras per machine. BTW, why would anyone want to jam GPS or GSM, and how would a laser pointer jam a radio?

It is very difficult unless you can funnel everyone down to a tight line like at an airport security check or an entry gate. If the subjects are allowed to approach the camera(s) from different directions, biometric software will not be able to capture them all properly.

You do realize that getting usable pictures of faces is difficult in a normal environment? For biometrics to work, the faces need to be captured straight on, with a clear view of all features and the picture should pretty much be zoomed in tight. Hats, hoods, sunglasses and other items that obscure the face will make it difficult for biometrics to "read" a face. Also, the angle and distance between the camera and the subject can adversely affect facial recognition.

It's true. Assuming you have a 12VDC camera that draws 150mA: A 24 gauge power wire can be run approximately 156 ft. A 23 gauge power wire can be run approximately 196 ft. A 22 gauge power wire can be run approximately 248 ft. Here's a link to a wire length calculator http://www.video-insight.com/Support/Tools/Wire-Length-Calculator.aspx

He's right up there with my favorite candidate:

Would something like this work? VideoEase CCTV Power-Thru Balun Part #: 500024, 500029 http://www.muxlab.com/products/ve_cctv_power_thru_balun.htm It would allow you to use CAT-5 for your cable, but I don't believe you could hook the other end up to a POE switch since the video signal would still be analog.