How to Solder a 1/4" TRS Plug
- 1). Plug in the soldering iron.
- 2). Cut open the speaker cable and expose the insulated wire inside. There should be two insulated wires and an uninsulated shield wire inside.
- 3). Strip a quarter inch of insulation from each wire. Bare copper should be exposed.
- 4). Unscrew the housing of the TRS connector. There should be three metal contacts inside.
- 5). Identify which wires should be soldered to which contacts. For home audio, the shortest contact carries the left channel's signal. The middle length contact carries the right signal. The longest contact connects to ground.
- 6). Apply a small amount of solder to the tip of the soldering iron.
- 7). Touch the wire carrying the left channel to the shortest metal contact. Place the soldering iron on top and add solder to the wire. Remove the iron and let the solder joint cool.
- 8). Solder the wire carrying the right channel to the middle length metal contact. Then solder the uninsulated shield wire to the longest metal contact.
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