HowTo-Color (8) / Hacking Electronics / Simon Monk / 236-3 / Chapter 9
CHAPTER 9: Audio Hacks
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The exception to this is for leads to loudspeakers. These are not screened because the signal has been amplified to such a degree that any noise the speaker cables might pick up would be undetectable.
Soldering Audio Connectors Stripping audio connectors is made more difficult by the fact that there is more than one layer of insulation. It is very easy to accidentally cut through the shielding. Nicking the outer insulation all around before stripping it will usually help with this problem. Figure 9-3 shows the sequence involved in soldering a screened lead to a 6.3mm jack plug of the sort often used to connect an electric guitar to its amplifier. The first step is to strip off the outer insulation about 20mm (a bit less than an inch) from the end of the lead and tease the shielding wires around to one side of the lead and twist them together. Strip about 5mm of insulation off the inner core insulation (Figure 9-3a). Then, tin both bare ends (Figure 9-3b). The jack plug has two solder tags: one for the outer part of the plug and one connected to the tip. Both will usually have holes in them. Figure 9-3c shows the screening trimmed to a shorter length and pushed through the hole ready to solder. Once the screening is soldered into place, solder the inner core to the solder tag for the tip (Figure 9-3d). These wires are quite delicate, so make sure the inner core wire has some extra length (as shown in Figure 9-3e) so that if the plug flexes, it will not break the connection. Notice that the strain relief tabs at the end of the plug have been pinched around the outer insulation. Finally, the plug will often have a plastic sleeve that protects the connections. Slide this over the connections and then screw in the plug casing.
Tip
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If there is a plug on the other end of the lead, remember to push the new plug enclosure and plastic sleeve onto the lead BEFORE you solder the second plug on, otherwise you will end up having to unsolder everything to put it on. The author has made this mistake more times than he cares to admit.
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