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FrozenGate by Avery

Electronics help...

o0ICE0o

o0ICE0o

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Not exactly laser related, but this seems to be the best place to put this... and you guys are good with electronics; so...

Long story short, I am modding a Game Boy Advance SP, by melding it with a PlayStation 2 controller for buttons, and adding speakers.

I have run into a problem...
I need an amplifier, or two, to power both of the speakers.
It is 2 channel stereo.

The GBA's battery is 3.8 v.

I need a circuit that would amplify the signal(s) from the 3.5mm audio jack.

I googeld, but got nowhere.
Thank you. :o

(Also, I have been gone for a short time, but the BRs are already in the 12x-s!! :drool: )

EDIT: The back of both of them say: 8 (Ohm) IL 271N-1
They are about 1 inch in diameter.
 
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LM386 low voltage audio amplifier IC.

I think Radio Shack still carries them, or DigiKey certainly has them.

I just looked, $1.49 each at radio shack.

Simple hookup with a breadboard.
 
...So two of these, one for each channel?

can I add a potentiometer to change the volume?
If so, is it before this IC, or somewhere between the pins?
How would I set this up to controol both IC's at the same time?

(THANKS!)
 
o0ICE0o said:
...So two of these, one for each channel?

can I add a potentiometer to change the volume?
If so, is it before this IC, or somewhere between the pins?
How would I set this up to controol both IC's at the same time?

(THANKS!)
Click to expand...


I'll post a picture and schematic for you in the morning.

yeah, they are single channel about 1 watt output.
 
Thank you very much for all of this help - I would have never found this on my own. ^_^
(goodnight, lol)
 
What is the minimum set up that this can use?
The space in the remote is very limited.
 
about 1 inch or so cubed (the 250uf cap is kinda tall)

why not put in a small jack for say a set of PC speakers off to the side? or better yet, headphones?
 
I still want it to be portable, and the holes for the joysticks that are no longer there would be perfect for speakrs, and i have two that fit.
1x1x1 would probable be do-able, with some awsome "boardless sodering".
 
Sorry for the double post...

What are the BARE MINIMUM components that this needs to operate?
After this, are there any that would make this work better, with a very small impact on the size?

Thank you. I would figure this out myself, but I am not good with circuits.
I can solder them together very well, but not really figure out how to make them.
:/
 
I re read those schematics, that is the bare minimum of parts, I can squeeze that on a stamp size PC board.
 
Oh.

Ok, then.

Thank you for all of your help!
It just looked like a lot to be the minimum.

I miss-assumed.

If I ever finish this project, I will post back here.
:D

EDIT:
Oh, WOW!
"Fig 1: LM386 Audio Amplifier with Gain = 20 and minimum part count"

Thats what I gut for using a ridiculous resoloution... small text is small, lol.
I didn't really look at those circuts...



lm386-20.gif



...To make shure:
Is Vin the battery, and Vs is the signal to amplify?
Or is it the other way around?
Also, pins 1,7, and 8 are just open?
Finlay, pin 3 gets connected before, or after the resistor?

Wow. I just hardcore newb-d. :(
 
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...I should have aksed this earlier, but what does the "not needed" part do if it's there?
What happens if it is not?

THANK YOU!
 
it's there to block low frequency noise. (its a "hum" filter)

I have built these without that (the hum filter) and they worked fine.

.05 uf is a tiny disc cap, it will only conduct very low frequency signals, then shunt them through the 10 ohm resistor.

Like a bandpass blocking filter.
 
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