- Wired, outdoor PC cameras? - 16 Updates
| Zaidy036 <Zaidy036@air.isp.spam>: Dec 26 12:02PM -0500 On 12/19/2022 12:09 PM, micky wrote: > USB conector? > **One facing the front, one to the right of that, and one mounted a foot > or two away, around the corner of the house, facing the side yard. Why use wired when Wi-Fi cameras are available? Google "Wi-Fi outdoor camera". Add "Solar" for more. Battery replacement time depends on use. If you have one outside light nearby can provide power from it. Some info here: https://www.bestbuy.com/discover-learn/top-8-things-to-know-about-solar-powered-security-cameras/pcmcat1637608496025 |
| Char Jackson <none@none.invalid>: Dec 26 11:56AM -0600 >The T368A and T368B thing is for rolled or straight-thru cabling. If both ends of a cable are 568A, or if both ends are 568B, it's a straight-through cable. If one end of a cable is 568A and the other end is 568B, it's a crossover cable, what you call rolled, below. Crossover cables are very rarely needed these days. All of mine are long gone. What's important is to pick a wiring standard and stick with it. I use 568B, but that's just personal preference and momentum. https://www.truecable.com/blogs/cable-academy/t568a-vs-t568b |
| Char Jackson <none@none.invalid>: Dec 26 12:06PM -0600 On Mon, 26 Dec 2022 06:29:32 +0000, Andy Burns <usenet@andyburns.uk> wrote: >round the back, and something stops working ... if you can retuerminate it with >a new plug, sure but patch cables are cheap, stuff not working is frequently >expensive ... I suppose it could be annoying if a connection comes loose, but it's not like it causes any damage. Just push the plug in and carry on, right? I get your point, though. One of these years I'll probably replace my barbless cables (or more likely just snip the connector and crimp a new one). They're not causing any problems, though, so it could be a while. |
| Ken Blake <Ken@invalid.news.com>: Dec 26 02:25PM -0700 On Mon, 26 Dec 2022 11:56:48 -0600, Char Jackson <none@none.invalid> wrote: >>uses a rolled cable (only if both ends are limited to 10/100BT NICs). >>GbE equipment has MDI/MDIX which can deal with either straight or >>rolled cabling. I had never heard of 568A or 568B before. Short of taking it apart, is it possible to tell which connector it is? |
| scott@slp53.sl.home (Scott Lurndal): Dec 26 09:34PM >>>rolled cabling. >I had never heard of 568A or 568B before. Short of taking it apart, >is it possible to tell which connector it is? It's the same connector (RJ-45) for both. 568A/568B are the standards for which wire goes to which contact in the (usually) female connector. Cables (with male connectors) are typically wired straight through or crossover (rare now). |
| Ken Blake <Ken@invalid.news.com>: Dec 26 03:15PM -0700 On Mon, 26 Dec 2022 21:34:34 GMT, scott@slp53.sl.home (Scott Lurndal) wrote: >>I had never heard of 568A or 568B before. Short of taking it apart, >>is it possible to tell which connector it is? >It's the same connector (RJ-45) for both. Yes, I know. I guess my question wasn't clear. > 568A/568B are the standards >for which wire goes to which contact in the (usually) female connector. Yes, I understood that from Char's post, >(usually) female connector. I thought (especially for crossover cable) that it was especially pertinent to male connectors. >Cables (with male connectors) are typically wired straight through or >crossover (rare now). Yes, I know. What I didn't know was that a crossover cable is one that is connected 568A at one end and 568B at the other. I was asking whether (and if so, how) I could tell whether the connections were 568A or 568B. I basically wanted to know that so I could tell whether an old cable I might have lying around is a crossover cable. |
| "Carlos E.R." <robin_listas@es.invalid>: Dec 26 11:46PM +0100 On 2022-12-26 19:06, Char Jackson wrote: > get your point, though. One of these years I'll probably replace my > barbless cables (or more likely just snip the connector and crimp a new > one). They're not causing any problems, though, so it could be a while. I have one such cable. It is perfect. it is used for temporary connection to my laptop, and being able to pull it off easily is a plus :-D -- Cheers, Carlos. |
| scott@slp53.sl.home (Scott Lurndal): Dec 26 11:08PM |
| scott@slp53.sl.home (Scott Lurndal): Dec 26 11:10PM >whether (and if so, how) I could tell whether the connections were >568A or 568B. I basically wanted to know that so I could tell whether >an old cable I might have lying around is a crossover cable. You can (a) look at the wire colors in the cable through the transparent connector and match them to the chart, or (b) plug the cable into a cat5 cable tester. https://en.wikipedia.org/wiki/Ethernet_crossover_cable https://en.wikipedia.org/wiki/ANSI/TIA-568#T568A_and_T568B_termination Assuming that whomever made the connector followed the wiring T568 suggestions. |
| Paul <nospam@needed.invalid>: Dec 26 06:27PM -0500 On 12/26/2022 5:15 PM, Ken Blake wrote: > whether (and if so, how) I could tell whether the connections were > 568A or 568B. I basically wanted to know that so I could tell whether > an old cable I might have lying around is a crossover cable. Ohmmeter. Check whether 1,2 on one end, goes to 1,2 on the other end. Or, whether 1,2 on one end, goes to 3,6 on the other end. The first is straight thru. The second is crossover. Of the eight wires (four twisted pairs), four of the wires are "legacy" material. 1,2 and 3,6 pairs were used on 10/100BT for the wiring. The remaining wires would not be doing anything. On the legacy stuff, a TX pair was wired to an RX pair. An RX pair was wires to a TX pair. That was the four wires. Whereas GbE is bidirectional on eight wires total. https://electronics.stackexchange.com/questions/132486/how-does-bidirectional-transmission-on-gigabit-ethernet-work And the waveform on GbE is "beautiful". It's PAM5. It would look even nicer, if we could see the PAM5 eye diagram on the Tektronix digital scope. Very colorful. https://www.edn.com/wp-content/uploads/media-1163595-134711-tmw03-04f2fig1.gif ( https://www.edn.com/what-pam5-means-to-you/ ) Paul |
| Ken Blake <Ken@invalid.news.com>: Dec 26 05:12PM -0700 On Mon, 26 Dec 2022 23:10:11 GMT, scott@slp53.sl.home (Scott Lurndal) wrote: >You can (a) look at the wire colors in the cable through the > transparent connector and match them to the chart, or > (b) plug the cable into a cat5 cable tester. Actually, a few minutes ago, I looked the one cable that I could easily find. Yes the connector was transparent and yes I could see that they were the same so it wasn't a crossover cable. But are the connectors always transparent? My memory might be wrong, but I didn't think so. |
| Ken Blake <Ken@invalid.news.com>: Dec 26 05:14PM -0700 On Mon, 26 Dec 2022 18:27:33 -0500, Paul <nospam@needed.invalid> wrote: >Or, whether 1,2 on one end, goes to 3,6 on the other end. >The first is straight thru. >The second is crossover. Thanks, but I don't think I need to do that. See the other reply I'm about to send. |
| Ken Blake <Ken@invalid.news.com>: Dec 26 05:18PM -0700 On Mon, 26 Dec 2022 17:12:15 -0700, Ken Blake <Ken@invalid.news.com> wrote: >that they were the same so it wasn't a crossover cable. >But are the connectors always transparent? My memory might be wrong, >but I didn't think so. My memory is apparently wrong. It just occurred to me that it would be very easy to look at the cables coming into my router. Yes, the ends of all four of those connectors are *all* transparent. What must have confused me is the part of the connector next to that end transparent part is opaque, colored the same as the cable itself. |
| Char Jackson <none@none.invalid>: Dec 26 09:11PM -0600 >> 568A or 568B. I basically wanted to know that so I could tell whether >> an old cable I might have lying around is a crossover cable. >Ohmmeter. Ugh! Just do a visual check. Put the two cable ends side by side. If the colors match, pin for pin, it's straight through. If not, it's most likely a crossover, but could also be miswired (not likely). You can use the colored pictures found online, as well. |
| Char Jackson <none@none.invalid>: Dec 26 09:21PM -0600 On Mon, 26 Dec 2022 21:34:34 GMT, scott@slp53.sl.home (Scott Lurndal) wrote: >>I had never heard of 568A or 568B before. Short of taking it apart, >>is it possible to tell which connector it is? >It's the same connector (RJ-45) for both. AKA 8p8c >568A/568B are the standards >for which wire goes to which contact Agreed. >in the (usually) female connector. Not sure what you're saying there. Gender has nothing to do with it. The two wiring standards (568A & 568B) apply equally to both genders, although patch panels, which are almost always female, are normally wired straight. The crossover role, if needed, is normally left for the patch cable, the link between the patch panel and the piece of equipment. >Cables (with male connectors) are typically wired straight through Right, using either 568A or 568B cable/pin assignment. >or crossover (rare now). Agreed. |
| scott@slp53.sl.home (Scott Lurndal): Dec 27 04:15PM >It would look even nicer, if we could see the PAM5 >eye diagram on the Tektronix digital scope. Very colorful. >https://www.edn.com/wp-content/uploads/media-1163595-134711-tmw03-04f2fig1.gif You ought to see the eye diagram for 400Gbe and 800Gbe with PAM4. |
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