- This topic has 11 replies, 2 voices, and was last updated February 14, 2014 at 11:22 am by Angel.
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February 8, 2014 at 1:56 pm #1057888
http://www.youtube.com/watch?v=a8cd0yIS7yc
The cable is only used for 12V DC power to a wall mounted router on the upstairs stairwell outside my studio/workshop (I put it there as inside the signal hardly gets anywhere as there are too many computers and other equipment with metal cases connected to earth ground which block the wifi).
I only used one of the cables, but I had already taped them together when they were used for some other equipment, and it was easier to pull the two cables through the wall than just one, and separate the one I am not using.
But to do that I need to be sure which cable is which. This tone generator and amplifier are widely used by telecoms engineers worldwide for this purpose, but what surprised me was just how much signal leaked out from the cable at only audio frequencies (to the point it wasn’t so easy to work out which cable was the correct one and I ended up also doing a continuity test as well).
With twisted pair cable (proper network/telecoms cable) it is far easier to work out which pair is correct as the leakage signal is confined more closely.
if you use this kind of flat cable to transmit much higher radio frequencies (that are used in modern computer networks) and then connect it to the rest of the house mains wiring, which is made to be safe but not for data communication, all those frequencies will get straight into the air, as well as contaminating earth ground which is often also used for signal ground (in metal framed equipment they are often combined for electrical safety reasons). This interference can be a great nuisance for many tens of metres around for those who enjoy using analogue radio equipment (and many people still do).
It could also make your computer network insecure – tapping into it might take a bit more sophisticated kit than my nearly middle aged ears and brain listening to the tone amplifier, but the principles of getting the data would be the same….
So if you are setting up a network in your house, either use good quality wifi equipment or CAT6 (Ethernet) cable, it is not that expensive and is not a major DIY job even if you have to run a few cables. If other folk in your house complain about the wires, there is lots of plastic trunking / conduit available to hide them in..
February 9, 2014 at 11:15 am #1278357Anonymous
I read recently it’s illegal in this country to wire your house up to a network other than casually stringing a network cable accross the house unless you’re a qualified electrician.
Is it the same im the UK?
February 9, 2014 at 11:39 am #1278359@Dr Bunsen 561198 wrote:
I read recently it’s illegal in this country to wire your house up to a network other than casually stringing a network cable accross the house unless you’re a qualified electrician.
Is it the same im the UK?
no, computer networks, telecom cable, burglar alarms and other signalling cable are normally classed as extra low voltage and can still be done as DIY jobs. There are some new rules which are a bit silly as they mean I am classed as a competent person for 230V and 400V industrial electricity work as well as telecoms/computers, but at home there are bits of mains wiring I am not allowed to work on :rant: which I could right up until 2005.
Not sure about other EU nations (Scandinavia may be stricter) but there is a safety rule that all telecoms/signal cable must be at least 150mm from other cables carrying strong voltage or other power cable (as even a 12V or 48V DC supply can short circuit and set a fire if there are not enough fuses), and that telecoms functional earth (rarely used nowadays) and protective earth (or signal ground and earth ground) must be bonded at some point (which is good for safety but not always for signal quality!)
With telecom cable you have to be a bit more careful as there is 100V or more when a phone rings, ISDN can have 120V on the pairs (this does bite), some other PABX systems use 120V on the pairs to strike a neon lamp on a standard telephone set as a message waiting warning (as this lamp can also be used to indicate ringing).
If its going outside to the PTT line there is a chance that a fault could have made a pair contact strong voltage (especially in rural areas where utility poles are shared between telecoms and power company). However this normally blows the fuse at the telephone exchange and the folk who have to work up poles and in access trenches half full with water tend to look out for this sort of thing.
A hit from telecom volts is rarely harmful from the electricity itself, but because distribution boxes are often at height or in inaccessible places, the reflex that causes you to move back can put you off the ladder/or out of the roofspace and result in other injuries…
February 9, 2014 at 8:32 pm #1278358Sure. I only heard this recently as I said and I think the reasoning is most houses here are connected to phone lines over ADSL and a network might be a conductor into the house but it just as easily be a ploy to keep electricians in business… 🙂
February 13, 2014 at 8:13 pm #1278353Just be yourself and do the same always 🙂
February 13, 2014 at 8:23 pm #1278360Okay Doc 🙂
February 14, 2014 at 9:19 am #1278354s’meet and greet inni’t.
February 14, 2014 at 9:52 am #1278361ehhhhhh What?
Speak english man :crazy:
February 14, 2014 at 10:33 am #1278355Your “job” is to meet and greet new members as they join then tear their clothes off after a polite amount of time. Did no one tell you?
February 14, 2014 at 11:10 am #1278362LMAO okay Doc, will do 🙂
February 14, 2014 at 11:17 am #1278356Wrong forum though eh
February 14, 2014 at 11:22 am #1278363yep
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