On 100 Mb Ethernet only 2 pairs of wires are used for data transmission (1-3 and 2-6). The remaining 2 pairs act like a shielding. If you switch the "shielding wires", the cable will still work, but the transmission wires have to be connected right. On 1 Gb Ethernet all 4 pairs are used for data transmission and all the wires have to be connected in the right order. Otherwise your device might be identified as 100Mb or in most cases it will not work at all. Thanks for the great tip with cleaning the battery holder!
i considered building one of these using a resistor network at one side - and a arduino etc at the other side - you can use the resistor network ( different values) as a byte value to detemine what pin is shorted to what other pin , and if all pins are connected , based on the resistance of each wire at the other end. for instance if one line reads 470k + 220k that means that 2 wires are shorted together and those two combined values are the faulty pair
Good idea. The are certainly a lot of arduino-base cable tester projects today, but when I built this thing back in 2010, I didn't even know arduino existed.
Duracell batteries are known to leak prematurely, sometimes way before expiring date. This is mostly in devices with a very low powerconsumption. Even cheap brands of batteries will not leak that quickly as Duracell does. Duracell no longer comes into the house here.
Something like a lithium thionyl chloride 3.6V cell or a pair of them in parallel would be a good idea if this was an infrequently used tester as they have extremely long shelf lives.
chris Thousands of feet. The LEDs will simply dim slightly with increased length. If it's 24 AWG wire, then 1000 feet of cable will add roughly 50 ohms (25 ohms in each conductor of a twisted pair) to each LED circuit.
On 100 Mb Ethernet only 2 pairs of wires are used for data transmission (1-3 and 2-6). The remaining 2 pairs act like a shielding. If you switch the "shielding wires", the cable will still work, but the transmission wires have to be connected right. On 1 Gb Ethernet all 4 pairs are used for data transmission and all the wires have to be connected in the right order. Otherwise your device might be identified as 100Mb or in most cases it will not work at all.
Thanks for the great tip with cleaning the battery holder!
Thank you for this. just made one, although not as elegant as yours, to do a quick test on some of my cables.. worked a treat!
Eric, the vinegar tip is very useful . Thanks for great videos
👌don't forget to change battery next month! smart idea.
i considered building one of these using a resistor network at one side - and a arduino etc at the other side - you can use the resistor network ( different values) as a byte value to detemine what pin is shorted to what other pin , and if all pins are connected , based on the resistance of each wire at the other end. for instance if one line reads 470k + 220k that means that 2 wires are shorted together and those two combined values are the faulty pair
Good idea. The are certainly a lot of arduino-base cable tester projects today, but when I built this thing back in 2010, I didn't even know arduino existed.
Duracell batteries are known to leak prematurely, sometimes way before expiring date. This is mostly in devices with a very low powerconsumption.
Even cheap brands of batteries will not leak that quickly as Duracell does. Duracell no longer comes into the house here.
Something like a lithium thionyl chloride 3.6V cell or a pair of them in parallel would be a good idea if this was an infrequently used tester as they have extremely long shelf lives.
Awsome
Nice :) Thumbs up :D
Alex
How long of a cable run will this work on?
chris Thousands of feet. The LEDs will simply dim slightly with increased length. If it's 24 AWG wire, then 1000 feet of cable will add roughly 50 ohms (25 ohms in each conductor of a twisted pair) to each LED circuit.