Build a mini-audio amp with your kids for Xmas

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Ran across this video while searching for something else. This is a great project for a parent and their child to build together! Very simple, straightforward and inexpensive. If you want to build a stereo amp, you'll need to buy two of everything. Radio Shack may have most of the parts...may. However, you can also order from Mouser, Jameco or Digi-key. You can use a speaker with a higher impedance, like 10, 12 or 16 Ohms but not lower (6 or 4 Ohms) as it will badly distort. The author does a great job of going slow, step-by-step through putting the components on a breadboard.
 
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Originally Posted By: sleddriver
Ran across this video while searching for something else. This is a great project for a parent and their child to build together! Very simple, straightforward and inexpensive. If you want to build a stereo amp, you'll need to buy two of everything. Radio Shack may have most of the parts...may. However, you can also order from Mouser, Jameco or Digi-key. You can use a speaker with a higher impedance, like 10, 12 or 16 Ohms but not lower (6 or 4 Ohms) as it will badly distort. The author does a great job of going slow, step-by-step through putting the components on a breadboard.
Heck, this looks like a great project for a childless loner who just wants to build things and learn more about electronics! Thanks for the link!
 
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Thx for sharing. Yeah, brings back childhood memories (in my early teens, I've built countless LM386 based amps for various usage: from high gain (up to 40) AF amp for Xtal radio sets to low gain stage for powered walkman speakers, etc. Memory serves: there's 4 different varieties of LM386, with NatSemi's LM386-4 being the highest output type of all, and that was one of the highly sort-after types that I dreamed of. it's still a very, very good beginners small power AF amp chip, highly recommended for kids audio projects. 2 things of note: (1) make sure you keep that zobel network on the output side...that is for proper maintenance of the output impedance throughout it's audio spectrum; (2) do not load it with speakers of less than 8ohm, for distortion will occur and it's very, very ugly. Q.
 
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Very cool! I love tube amps and have rebuilt quite a few classics. My son is only 8 months but am looking forward to doing projects like this with him if he's interested down the road...
 
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This DIP-8 based small power amp does not have any heat-dissipation issues. Unless you are able to obtain LM386-4, which comes close to [email protected] (THD10% if memory serves), then you might need a heat sink. typical operational mode @ 9V or 12VDC on run-of-da-mill LM386, you don't need heatsink at all. Q.
 

OVERKILL

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Fantastic! I have a small stereo amp I built back in high school somewhere that I should dig up and try to recreate with the kids. Thanks for the inspiration!! thumbsup
 

CT8

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Awesome doing that with your kids. I used to do stuff like that with my kids. It usually gets them thinking. And learned skills that last a lifetime.
 

sleddriver

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Simple circuits like this are a great way to teach kids about electronics, give them something to do with their hands (cut, strip wire, push it into the holes, be mindfull of polarity, etc.), and couple it with something alot now have: MP3 players. Plus they get to show it off to their friends & family. Another cheap chip to play with is a 555 timer IC. Lots of neat things to do with one: bulb/LED/1 W LED flasher, asynchronise dual flasher, siren, time delay. The output alone will drive a relay. Draw the schematic out big like 11 x 17 and use a toy car to show current flow. You can make a list of the different pins and label them. As they hook up wires and components, have them check off both ends of the wire as they go. This helps prevent mistakes. You can also make this an electronic puzzle...set it up, use it, then dissasemble it and let them do it themselves. Now that you have an amp, build a siren with a 555 and feed it into your amp!
 

sleddriver

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Here's a very simple LED ckt using a 555 timer IC + a blue LED. Instead of quickly turning on & off, it slowly ramps up to full brightness, then back down to zero. This would make an interesting night-light for your kids. By varying the resistance & capacitance in the timer, the flash rate and turn-off/on times can be varied. You can also get out the calculator and have them crunch RC time constants if they're old enough. The point is to let them have fun with it, try different color LED's, hook them up in parallel, try different resistor values, then different capacitor values to see the effect. (You won't need the 2n2222 transistor with red, yellow, or old-style green LED's as they don't need as much voltage to drive them. But buy spares!) With older kids you can introduce the concept of solid-state light generated by the combination of holes & electrons in the silicon. Use a magnifying glass, telescope eyepiece turned around or camera lens turned around to examine the tiny chip inside the water clear LED's (power off of course). Jameco may have a 555 and or LED experimenters kit. Have fun with it and be creative. If you have a plastic toy reindeer around you can install a red LED in the nose and have it ramp on/off! Merry Christmas!
 
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