I wouldn't have expected your Epia to have problems under normal circumstances either.
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I wouldn't have expected your Epia to have problems under normal circumstances either.
d00d =) that doesnt answer my question. Because some car audio shops have convinced me that if I plug in a CD player into the receiver and I charge the CD player at the same time from the car battery, the CD player will burn. To be honest I never thought this was possible before this.. but now I think they are probably right.Quote:
Originally Posted by DodgeCummins
Let me put it this way. My Pioneer stereo and a number of folks on this site's stereos are used in this way. Some through inverters some like mine through DC-DC.
If yours burns up equipment, then your stereo is the problem.
If you don't have enough faith in the quality and safety of your Head Unit, then toss it and get a real one.
Also you still haven't stated what brand unit, or what kind of car, or if it is positive or negative ground system etc.
A cell phone might explode if I use it at the gas station...but not likely.
You might try to find someone with some electronics knowledge...and not the monkeys at the car stereo shop...I don't even waste my time talking to them.
You need to talk to someone that can take some measurements on your stereo gear, your hookups etc.
The fact you are blowing fuses raises two red flags...one-that something is very wrong, and shorting out, two-that you have limited knowledge about the cause.
The only thing that I can guarantee, is that if this happened to me I would,
a) take my digital voltmeter and start testing.
b)check out the schematics of the HU and everything else,
c) check the voltage potential between the mobo and vehicle ground,
d) check the voltage potential between that aux in jack and vehicle ground,
e) check the voltage potential between the aux jack and the mobo.
f) do loaded voltage measurements of the mobo power supply.
g) do some continuity tests
h) take some cheap portable tape player or something, and test the aux-in.
i) ensure the engine block is well grounded to the frame/chassis
j) ensure the battery is well grounded to the frame/chassis
k) ensure the stereo is well grounded to the frame/chassis
My only guess on the subject, is that the stereo has a bad ground, or short, and is using whatever is plugged into the aux jack as the ground, if the one ground is not connected to the other ground, then your soundcard ends up being used for the ground...it can't take the load, and burns out.
Surely there is someone where you live, with real electronics knowledge...
Alrighty, thanks. That clears up one thing. So those folks and the audio shop didnt know what they were talking about.
I asked them that when I suspected something was wrong with the setup, and asked them to check the wiring. They simply said.. no they wont check the wiring. I asked why and then they went to great lengths to explain that if I connect something to the battery in the car and put it in the stereo jack on the receiver then it will short. They havent seen my car or the stuff I have in it yet at the time. *shrug* they seemed confident.
I did take an ohmmeter and connect one end of it to the battery -ve and the other end I just plugged into the aux-in and I had an ohm of 0. I thought it was shorting because the +ve signal from the stereo plug was touching that ground in the receiver.
When I asked the car stereo guys about it, they told me that all car stereo setups are this way. Heh.
THat's why I was looking into building a circuit with a capacitor to separate the DC voltage coming in directly from the battery to the aux-in but I found a ground loop isolator and I figured this has transformers inside and would do the job.. which it did.
By the way, as I said before.. my receiver is one of those el cheapo ones. I dont even remember what brand it is.. something with funky names. I only bought it after testing it because it didnt have those noise coming in when you're connecting a walkman into the aux-in input.
If you had an ohmeter measuring resistance, then it makes sense that there would be no resistance from batt- to the aux in jack...at least the outer part. (the common...the base...the - )
If you were to use a voltmeter, then hopefully you would read zero volts with that same hook up...that means that vehicle ground is the same as chassis ground on your radio...that is a good thing.
Next i would do the same test on the computer thing.
I guess what the monkeys said was partially true. If you were to hook a wire from the battery + and touch the receiver aux in...that would be a short...duh...you knew that much I am sure.
There is more electrial theory I could get into...but that won't help.
The reason I keep saying that you should be able to plug it in and go (If everything is wired correctly) is that the aux out of your computer only puts out a few volts and maybe half an amp...that in not even enough juice to visibly see a spark, let alone burn out any parts.
The aux in on the stereo is set up the same way. low voltage and low amps...there is nothing there with enough power to do any damage.
However is something is miswired, then you could have more volts available and/or more amps available...that would zap anything you plug into it.
Stick that stereo plug into the radio (while turned on) and measure voltages from ground to all three parts of the plug...
If we knew the brand, then maybe we could look up the specs on the internet...
Since it has been 4 days since this topic started, surely you have looked at the unit...or is it so generic that it doesn't even have a name...like metrosound, or sounddesign,
Can I ask a question, why are you even mucking about with this Headunit? if it is blowing your soundcard when you connect it to the Aux in then it is *****ed.Quote:
Originally Posted by masch
Remove your headunit, find a bin, throw it in, then go buy a Kenwwod/alpine/Sony/JVC etc etc
Dont muck about with cheap *****.If you cant afford a new HU then go buy a cheap amp and plug it in there.
I cant belive you are trying to test the wiring on this HU.
Even if you fix the problem with power going to your Aux in who knows what elese might happen.
True...
That's some great advice sunglassesron. =P Too bad if I put it in the bin, and get a preamp, I wont have radio at all.
Dodgecummins, I checked all around the outside and it doesnt have a brand name. Perhaps if I take it out I could check at the back but I havent done that yet. If I had a digicam I'd take pictures to show you.
So basically thanks to you guys I've established 1 thing:
It is OKAY to plug in a player that's charging from the same car battery as connected to your headunit and connect that player to the headunit via the AUX-in input.
That means the guy at the car accessory shop didnt even know what he was talking about.
So back to the original question, as I have already resolved that soundcard blowing up problem by putting a ground loop isolator in between, however I notice this distortion or noise when I pump the volume up. I thought GLI's are supposed to filter those out.. or could it be because of the (supposedly) messed up wiring on the headunit?
Alright, your wiring is screwed up someplace. We all know that. The only way that the scenario you are describing could happen is if there is power being transmitted where no power should go, ie through your rca/miniplug cable. So do one of the following.
1. To see if the computer is the problem, try using a a CD player with your radio
2. To see if your wiring is the problem, try either wiring it correctly or buying a proper wire (available at Circuit City, etc, and probably cheaper then the wide variety of fuses you've purchased.)
3. To see if your head unit is the problem, hook your carputer up like normal but listen to the mobo with headphones or hook some pc speakers or something up.
This will isolate what component is the problem. My guess would be either your wiring is improperly insulated and touches a hot wire someplace, or your head unit has serious and unsolvable issues. If you can't diagnose the problems with your head unit yourself, there's no way we can help you fix them over the internet.
It is some great advice. If your computer works fine when you listen with headphones, or if your CD player goes BZZZT, get that thing the heck out of your car. I'd stomp on it a few times, personally. Screw radio...I've been without radio for 6 months just because i was too lazy to extend the antenna wire when i relocated my head unit...if you are choosing radio over a working carputer then you're on the wrong forum. Also, if you get your carputer running, you can always add computer controlled radio later.Quote:
Originally Posted by masch