bought a JL 300/4, for 100 dollars, but broken. can she be fixed?! pics inside.

nathanh
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Well, not gonna throw down any racist bashes here, but just for facts, the guy was a hispanic... LoL.

well the amp bench tested fine, couple of the switches weren't working right, but overall, it worked for 100 dollars, kinda figured i was getting a 100 dollar amp. but anyways, as sceptical as i am, i brought it home and opened it up right away.... and found a shat load of this!

CIMG0973.jpg


yes, 1 ply toilet paper... not gonna drop a racist bash, but one ply none the less. well i thought it was kinda odd that it was all packed in there, so i took it out. and guess what i found under it!

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yeah i thought it was pretty cute too... wish i woulda spent more time bench testing... huh... well that kinda sucked, so what should look like this...

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looks kinda like this:

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yea for me!!! lol toilet paper... and how did they get it to work? maybe it's just one channel that doesn't work. no wonder he was being so carefull with it. crafty little bugger!

lol so my question is, can i just hit the back of the board with a soder gun and have it re-attach?

CIMG0966.jpg


or how about taking some steal weld (that gray puddy stuff that goes rock hard after cured. electric conductor? dont know.) and pressing it into that so the two terminals hit.

EP-COPPER_medium.jpg


there are a ton of electrical conductive epoxys and glues... but i think i would rather soder it then play with a bunch of expensive chemicals.

well imput would be good. and let me know what you think about this switch layout.

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are those switch layouts going to work for me? i wanted to run my lows or my mids off this amp. if the switch layouts are f'ed, which ones should i look into? i am running a alpine 9886, and plan on running active crossovers from pheonix gold. incase, you need that little tid bit of info.

the switches look something like this with the cover off.

CIMG0968.jpg


 
sorry, the switches, they don't move. they are all stuck like that... that would be a bit of usefull info i suppose. lol.

so would i just tag the back of the board with a soder gun? i have done little piddly stuff before, but never on a board.

 
wow thats beat to shit.

find the #s on that cap, buy a new one, solder it in.

then you're probably looking at a few new switched to replace those ones.

 
hummm... any way to use the old cap? really i should buy a new one... but i am a bit lazy and don't have any idea where to find a new cap. and this amp will live! ****it, it will be the best 100 dollars i ever spent, well aside from that happy endings massage parlor... but we wont go into that one. lol

 
found a cap... um, old one is a samyoung 25v 2200uf... i found one, but...

CAPACITOR 25V 2200UF LOW ESR HITEMP,HIFREQ.RAD. 12.5DX40LMM - 25V/2200UF/R/ESR - Distributed BY MCM

what does that mean?! like really?! lol anyone know if that will work? i don't know what the r and esr mean. also i have read on a couple sites that people have upgraded their amps by replacing the lower capacitor by like a 30v 3000uf. don't know if i wanna play with that though.

 
25 volts is the breakdown voltage for the capacitor. Don't go smaller than what's stock, as it might cause failure of the dielectric material inside the cap (the stuff that separates the plates).

2200 microfarads is the capacitance.

ESR is the equivalent series resistance, low ESR is desirable in an electrolytic.

You could try replacing the old one, but I'd probably just buy a new one to remove it as an unknown for troubleshooting. That amp has lived a hard life, a few new parts wouldn't be bad //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 
****, Amp is too fged up.
Actually, if that's all that's wrong, it's an easy fix...switches and caps are easy //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Where things get fun is re-etching traces, rebuilding the PCB itself //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 
oh man i am stoked! check this shananaganz out!

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anything i should be looking for as far as failures here?

i have no idea... like i don't understand how that happened. i dont... like, did someone actually try and physically do that? cause like, there are two plastic peices... but like... i don't know.

 
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