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Title: Build an LM386 Amplifier

Class Size: 5

Cost: $20 (estimated)

Pre-requisites: none

Minimum Age: XX and up (under 18 must have parent present)

Learn to solder an LM386 amplifier. 

Order of Build:
  *Resistors
    * 1K (brown-black-red)
    * 4.7k (yellow-violet-red)
  * IC socket
    * Orientation isn't critical, but should be observed
    * Note that pin 7 doesn't have a solder pad. No need to solder it.
  * Ceramic capacitors (C1 & C4, both 0.1 uF)
    * No orientation
  * 3.5mm jack
  * External connection pins
    * A+/A- (audio input?)
    * +/- (power) (if using a 9V clip, just solder the clip directly instead of pins, but you'll want to hot glue some strain relief because it **will** fail eventually, otherwise)
    * S+/S- (speaker)
    * Cut the pairs of pins off of the 6-pin strip
    * Solder in one pin, adjust fit if necessary, and then solder in the other.
  * LED (D1)
    * Long lead toward the triangle, short lead toward the line
  * Power jack (J3)
    * Solder one pin, adjust, solder the other two
  * It may be in your best interests to insert the LM386 into the IC socket at this point. The caps & pot make it difficult to insert if present.
  * Electrolytic capacitors
    * Long lead positive. 
  * Potentiometer
    * Cut off the anti-rotation tab
    * Solder one pin, adjust, solder the other two.
  * Speaker
    * Use two headered wires. cut off headers at one end, and strip the remainder
    * Solder stripped wires to tabs on speaker
    * Insert header pins into S+ & S-
  
Options/Hacks:
  * External speaker (i.e. a cabinet or something)
    * Wire up header wires to a 1/4" jack instead of the speaker
  * Additional gain
    * Simple way: wire up a capacitor between pins 1 & 8 of the LM386
    * adjustable way: wire up a 5k potentiometer between pins 1 & 8 
  *  Power switch
    * Wire up SPST switch between power source and + on PCB