At the beginning of World War II, Hedy Lamarr and the composer George Antheil developed a patent for a radio guidance system for Allied torpedoes that used spread spectrum and frequency hopping technology to overcome the threat of jamming by the Axis powers. Although the US Navy did not adopt the technology until the 1960s, the principles of their work were tied to Bluetooth technology and are similar to the methods used in legacy versions of Wi-Fi. Nowadays, telecommunication technologies are widely extended across our society. In this context, we propose the following activity:
Set up a wireless network and set your own networking cable following the steps below.
Networking cables with RJ-45 modular connectors are made of UTP (Unshielded Twisted Pair) flexible cable. UTP, in turn, is formed by 4 pairs of twisted conductors, all of them with coloured insulation. One of the conductors in each pair has a set colour, and the other one is white with traces of the colour of the other. A typical subset of these colours is:
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Orange. White/Orange. Green. White/Green. Blue. White/Blue. Brown. White/Brown. |
Steps:
- Cut a piece of cable of the desired length for your networking cable.
- Strip the cable jacket about 1,5 cm from the end where we are going to connect the RJ-45 modular connector. We need to be careful so as not to damage the insulation of the wires inside. We will use a crimping tool for this.
- Align the inside wires, along with their individual insulation, so that you can introduce them in the modular connector. The order should be as follows. Once the wires are aligned and put into order, we will cut their ends as straight as possible to even them out.
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White/Orange. Orange. White/Blue. Blue. White/Green. Green. White/Brown. Brown. |
- The RJ-45 modular connector should be in the right position: the contact pins on top and the latch, under. Then, carefully insert the wires all the way into the modular connector. The wires should be aligned in the upper end of the modular connector, just below the golden contact pins. Make sure that all wires are inserted all the way into the connector. Check the order of wires taking into account the "point of view" of the connector:
Introduce the RJ-45 modular connector inside the crimping tool and squeeze so that the golden contact pins are perfectly introduced and the wires are secured inside the connector.- Next, we will repeat the steps on the other end of the wire.
