Amp putting out DC voltage.

[xmakeafistx 10+ year member]

So far I know that this is a problem, but how would I go about fixing this?

I took gut shots of the amp, if these are needed for a response, let me know. I have no idea where to start, I am terrible with any sort of electronics knowledge.

I also have another broken amp laying around..

Click to read more...

 

[bubbagumper6 5,000+ posts]

Not really something you can fix especially since it sounds like you have no idea what you're doing...not trying to be mean, just honest.

 

[mast240 10+ year member]

a lil more specifics on your actual problem?

 

[xmakeafistx 10+ year member]

All I know is that when I plugged the amp into the subs, it made them pop up as if you were to use a battery to send it voltage.

Its a pretty cheap jenson 300 watt two channel amp, got it for free was looking for something to work on. & I totally understand bubba, but looking for somebody to kinda guide me through it, unless its not that easy.. lol.

There is no burn marks on the board that I can see, everything seems to be in fine condition.

 

[mast240 10+ year member]

have you actually checked the output with a DMM?

 

[xmakeafistx 10+ year member]

No, I have not. Just assumed from what it was doing to the sub, It was not giving out any actual sound output.

 

[mast240 10+ year member]

check your output voltage on your speaker out terminals... bot AC and DC... you should be reading only AC amperage (your DMM will most likely read a very small amount of DC, but this is normal)... if you are getting a sustained amount of DC voltage, then the amp is most likely screwed.

some of the cheaper amps will tend to "pop" subs when they first receive remote power.... due to inefficiency... but how are you setting your gains?

 

[Pyro_By_Nature 5,000+ posts]

If the amp is sending out steady DC voltage, one or more of the output transistors have likely taken a ****. Honestly, it'd probably cost you more to replace the fets than to just replace the amp entirely. A 300 watt jensen amp goes for what, $10-$20 on ebay?

 

[xmakeafistx 10+ year member]

I see, I figured I would have to replace something, I was hoping maybe it would be a solder job lol. But yeah, its not like I was depending on the amp, just had it sitting around, thought it would be nice to have something to do.

I also have an old school pioneer GX series 4 channel but everytime I put a fuse in it ******* blows out on me. Somebody told me my fets are probably bad, or my power supply..

 

[bubbagumper6 5,000+ posts]

Repairing damaged amplifiers is generally beyond the scope of the expertise here and even if you happened to get someone knowledgable enough to help you, it would be very difficult to troubleshoot over the web. Plus I doubt you have access to the proper tools you need //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

Definitely check to make sure that wasn't just a turn on thump you heard though.

 

[xmakeafistx 10+ year member]

I'm almost positive it just wasn't a pop, the cone like stayed all the way up until I unplugged the amp from it, also tried playing music didn't come through.

& the school I attend has many electronics engineers and I would assume they have the tools and expertise to help me possibly.. obviously just talking out of my *** though, not sure how much skill/practice this would take.

It would give me something to do during my middle of the day release..

 

[bubbagumper6 5,000+ posts]

Then follow this link and start learning. Basic Car Audio Electronics

He has a section for amplifier repair but he has a much larger, more complete repair tutorial you can buy. If you're serious about repairing any amplifiers you should buy the tutorial, it's great and Perry (the author) is very nice and offers some email support.

 

[xmakeafistx 10+ year member]

that is great, thank you very much for the info. This should help prepare me for the classes i'll be taking on it next semester.

 

[bubbagumper6 5,000+ posts]

that is great, thank you very much for the info. This should help prepare me for the classes i'll be taking on it next semester.

No problem. Out of curiosity, what are going into?

 

[xmakeafistx 10+ year member]

I'm mainly getting into IT, but hopefully also doing Electrical Engineering on the side, along with sound. Of course this is all after I get all of my IT stuff out of the way..

once again this is all very general thought.