Pocket Protest Audio Amp - LM386
- Thread starter zeturi
- Start date
zeturi
DEMON PIE!
Yes it is. Fourth post down: viewtopic.php?f=33&t=442&start=190
I'm wondering if someone could help on this. I followed the diagram above and hooked the amp up to a 7.4v line but I get absolutely nothing sound wise when I turn on the N64 I've attached it too.
Heres a couple of pics of the amp I built:
now the only difference in the parts I used listed was that I used a 220UF 25v cap instead of a 16v one.
I've also checked that power is getting to the amp but I just can't figure out why I get no sound whatsoever?
Heres a couple of pics of the amp I built:
now the only difference in the parts I used listed was that I used a 220UF 25v cap instead of a 16v one.
I've also checked that power is getting to the amp but I just can't figure out why I get no sound whatsoever?
ShockSlayer
Probably SS
I'm inspired to make a physical diagram of this audio amp.
ShockSlayer
Probably SS
Wouldn't be any problem at all.
SS
SS
bud
DAT ASS
Built one today. Got nothing. Speaker is connected to the positive and negative poles if the capacitor respectively. Amp is getting 4.99v from the n64s 7805. Both audio channels are connected to the same line. Funny thing is the potentiometer controlled the audio from the tv when I had the n64 connected to the amp and a tv at the same time. 
ShockSlayer
Probably SS
budnespid said:Built one today. Got nothing. Speaker is connected to the positive and negative poles if the capacitor respectively. Amp is getting 4.99v from the n64s 7805. Both audio channels are connected to the same line. Funny thing is the potentiometer controlled the audio from the tv when I had the n64 connected to the amp and a tv at the same time.
Nay, you're doin' it wrong. Negative on the speaker goes to common ground, positive on the speaker goes to negative on that cap.
SS
ShockSlayer
Probably SS
Figured this might be worth throwing in there:
Different way to wire it up, this is Ben's diagram.
Benheck wired up two of these and used a dual potentiometer to get stereo sound in his Wii Laptop.
SS
Different way to wire it up, this is Ben's diagram.
Benheck wired up two of these and used a dual potentiometer to get stereo sound in his Wii Laptop.
SS
ShockSlayer
Probably SS
Alright, this is one I wired up today:
As you can see, this thing can get pretty tiny.
Note: Don't use a GC slider for your 10k pot, it sounded terribad. The 10k pot actually affects how the sound, uh, sounds, I had to change to a different one, then finally a trimmer. That said, all of mine were scrap ones, so if you actually buy a good one then you'll be fine.
Now then, if you were to, oh, I don't know, wire up a headphone jack straight to this amp?
You'd blast your ears out.
The amp is designed to drive a speaker, not headphones.
It's best to have a resistor on the headphone jack in order to make it quieter, but you can't just add one, because you'd be adding a resistor to the speaker as well, making it quieter. You have to take advantage of the switching that goes on in the headphone jack.
I figured this out at MR CT, then Wyatt ate the amp and I didn't build one of those amps again till recently I guess.
The resistor shown is a 10k one, but I stepped it waaay down to a 100 Ohm and it sounded fine. It depends on your preference, you can make it as regulated or unregulated as you want, Heck, you could ever have another pot on this line so you can adjust it at will. XD
This only works for mono input, I think. It's wired so you get mono sound in both ears though.
Do exactly that, and you get full amp output to the speaker, and regulated output to the headphones.
SS
As you can see, this thing can get pretty tiny.
Note: Don't use a GC slider for your 10k pot, it sounded terribad. The 10k pot actually affects how the sound, uh, sounds, I had to change to a different one, then finally a trimmer. That said, all of mine were scrap ones, so if you actually buy a good one then you'll be fine.
Now then, if you were to, oh, I don't know, wire up a headphone jack straight to this amp?
You'd blast your ears out.
The amp is designed to drive a speaker, not headphones.
It's best to have a resistor on the headphone jack in order to make it quieter, but you can't just add one, because you'd be adding a resistor to the speaker as well, making it quieter. You have to take advantage of the switching that goes on in the headphone jack.
I figured this out at MR CT, then Wyatt ate the amp and I didn't build one of those amps again till recently I guess.
The resistor shown is a 10k one, but I stepped it waaay down to a 100 Ohm and it sounded fine. It depends on your preference, you can make it as regulated or unregulated as you want, Heck, you could ever have another pot on this line so you can adjust it at will. XD
This only works for mono input, I think. It's wired so you get mono sound in both ears though.
Do exactly that, and you get full amp output to the speaker, and regulated output to the headphones.
SS
