I was triing to clean up my center console the other day and moved my booster from inside the console to the outside, passenger side. once I did that I have a very loud and obnoxious buss in my raido. If I plug in and play my I Pod directly into the booster, no noise . I have grounded the raido, booster, even went as far as grounding the sheilds of the RCA cables (and tried different cables) into the booster. That seemed to quiet it up a slight bit but still buzzes when the FM, CD is on.
I then went to raido Shack and picked up a noise supressor (inline capacitor) Still didn't help.
I am begining to think Ignition or Alternator? Every thing was fine till I moved the booster from inside to the outside. This happened once before but not as severe, I just moved a few wires around and it went away.
Any ideas??

Here is the link I found good for the DIY guy who knows enough to be dangerous.
http://www.bcae1.com/

The sound you hear is the ignition and alternator. That does not mean they are bad. If it only does it with the radio and not with your ipod, the most likely problem is the radio ground. Check the ground wire terminal. Find where it is grounded and clean the connection. It should get better. Ground the booster and radio to the same chassis screw.

Take the radio out and listen to your car.

Yep I did all that, I have a #8 grounding the booster thru a 10mm bolt on one of the dash mtg bolts. I took the radio ground to the #8, even soldered the terminals. then I even grounded the radio chasis with the support band and bolted it ti the dash brackets. Do you think by some chance the intrenal filter in the radio failed? I was going to buy a cheap o radio and see if it stops?

You're absoultly right Elliot, Nothing beats the scream of the V-8 when wide open but I have to keep the wife entertained when on the WCR ride to crater lake

all of your audion equipment needs to be grounded at the same point. keep the rca cords away from any electric wires [do not bundle the power wires with the rca cords]

Did that too

does it do it when playing a cd?

YES Any time the RCA cables are plugged in and he engine is on it buzzes.
FYI I also removed the Bosch-4 Sparks and went with stock Delco plugs. But I cant remember when I did what

you need to run resistor plugs and restistor plug wires.

and check to see if any of the plug wires are close to any power wires

Ya, Im sure they are all resistor type plugs and wires. Everything was fine and well til I moved the booster. Are you gonna be at the WCR?

nope

calling you now

Tony,
Does the buzz go up and down in frequency with RPM's? If so an inline filter kit will help a lot. Got one from Radio Shack many years ago and it worked. It has an inline inductor and a capacitor and instructions in how to install. The inductor goes inline on the power lead and the cap goes from one side to ground. You mentioned you got a cap to go inline from RS, but not sure if you got the right stuff. A cap inline will not filter any "noise " out. The people at RS these days don't understand electronics very well from my experience lately. I went in some time ago looking for some diodes and asked the young guy where they had them, he pointed out a cabinet - I went over and it was resistors. LOL!!! Had to look around and find them myself.
Tom

This filter is sometimes called a pi filter because it's schematic sort of has the shape of the Greek letter pi (one inductor & two caps). FYI.

Did you change anything on your power source wire or ignition source wire?

Sometimes adding a fuse or cutting and reconnecting the main or ign wire can cause resistance or even going to a longer wire can put a bit more load on the source attachment point and might be putting it close to the max load for the fuse! Also using a fuse or wire on the ground that is smaller than than the source wire can cause a problem!

Just throwing it out!!

When I installed car stereos back in the day, I always kept the ground wire as short as possible and never spliced into a ground to lengthen it. Solder and shrink tube if I screwed up and had to. If I had a buzz I always suspected a bad ground.

When you say booster do you mean amp? When I did it for a living anything called a booster was cheap stuff. Things might have changed in 20 years.

Hi Guys,
Thanks for all the replies. Yes the frequency of the Buzzing does go up and down with the RPMs, also comes in louder when my electric fans kick in. The Capacitor (noise supressor) does have a ground, it was a cheap-o for $8 bucks, are there better ones?
Also, when I say Booster I do mean Amp, yea, I'm old school. I will be home tomorrow night and give it one more once over I'll ground the grounds, and bring a new supply voltage line to the radio.

Ahh, The one I have isn't that advanced, I'll look for one of those.

I doubt it'll fix your problem. Did you rotate the booster 90 degrees when you moved it? You might want to try a different mounting location/orientation. I'm ASSUMING you don't have a ground loop.

Tony,
If you have a Haynes manual, go to pages 140 and 141. Under paragraph 50, second paragraph down sounds exactly what you are having. It says see figure 10.59, but should be 9.59, top left on page 141. The Bosch alternator has a cap on the rear of the alternator. Because you have a V8, maybe yours doesn't. Pretty easy to check anyway. With alternators, alternating current is being generated and requires diodes in a bridge network to change the AC to DC. There is always some "ripple" or AC component on the DC coming out. Maybe you have some diodes going south and the ripple is getting worse. The amp just amplifies the ripple because it sees it as a signal the same as a signal from the radio or CD player.
Tom

I don't see how adding parts is going to fix this if it did not do it before the booster was moved and nothing else has changed. Pretty much has to be a connection is different, like something came loose or didn't get hooked back up the same. Or the way it was mounted was grounding the case differently.

OK I've been doing some reading on noise supressors.
I found this one
http://cgi.ebay.com/SCOSCHE-CAR-AUDIO-NOIS...R-/360310563137
which seems to be the direction from where the noise is comming from. When I disconnect the RCA cables the noise goes away, so for $15 bucks I'll try to see if this helps.
I didn't rotate it form its original possition, but I really feel I disrupted something by moving it.
I'll know more when I get home tomorrow.

Do the RCA's run parallel to the power cable? or Are the RCA's coiled in a loop? Both will cause the induced noise. Run them perpendicular to the power and in a figure 8. The biggest problem with RCA noise reducers is you will loose fidelity on the high and low signals.

They did run paralell with the #8 power line to the amp, but during my quest for triing to stop the noise I moved the cables, ran new ones in the air, grounded them, you name it I did it.

Usually grounding the RCA's does more harm than good. You should only ground the radio side. But that can cause a ground loop and induce noise too.

I'm thinking you should move your booster (amp?) around and see if the noise level changes.

If you have an old walkman. You can remove the tape head and extend the wires. Press play, put the head phones on and wave the head around your equipment. the head will pick up the source of your noise. You will hear the engine/alternator noise when you get the head close to the source. once you pin it down, make minor adjustments to the mounting, grounding , wiring until you hear a difference. I have a walkman setup for this from when I managed a car audio shop years ago.

Sounds to me like the problem is RADIO SHACK.
Get some real wires for signal. Anything from Radio Shack is going to give you problems. I wouldn't use their connectors, their wire even, I wouldn't use their solder or their soldering iron. -It's all built to ruin what you have. Go to a real electronics store and do it right or you'll forever be messing with it. I would use Noble brand insulated crimp connectors and an rca cable that wasn't made in china.

Today's Radio Shack cables are very well rated. They have excellent bandwidth & good strain relief.

Sounds to me, no pun intended, that you broke something. No shit. There's a bad connection somewhere. It might even be one of the jacks on your rigs.

Excellent suggestion. I need one of these.

Don't you mean that ungrounding the RCA phono connectors (or going to a floating chassis) will eliminate ground loops. The shielding must have zero current flow.

some drain wires are shunted to the shield. When this is the case, a ground loop can form on the signal ground. The cheap thin RS RCA cables have very little shielding. These do not protect from EMF noise.

I should ask what brand and how old is the radio? if the radio amplifier circuit board looses its ground, noise can happen as it uses the RCA shield as a ground path to the booster (amp). The RCA ground loop isolator can eliminate the noise at the cost of fidelity.

At this point I would first consider splitting up the amp and radio ground wires and screw them seporately. sand the paint down at the connection point and drive a new screw into the chassis. You may have too much ground potential going through your existing connection.

So the ground is floating? It is a car after all.

BTW, what's a drain wire?

The RCA ground can be floating but generally it is bonded to ground at the head unit. The shield carries half of the audio sine wave, so there will be trace current flow. On most amplifiers the shield is floating and not connected to the chassis. In the cases when they are bonded, it is usually through a high resistance circuit. This helps to isolate the audio signal from the chassis ground. In many cases when the two component's RCA cables are at the samp electrical potential, this creates the ground loop and causes noise. An RCA ground loop isolator is simply an audio transformer that keeps the electrical ground seporated. Because the low voltage audio signal must drive the primary coil of the transformer, signal quality is effected. Noticeably on bass frequencies and somewhat on high frequencies. This will directly alter the audio signal on the secondary coil of the transformer.

A drain wire is the ground wire on a shielded cable. They are designed to absorb transient EMF and shunt it to ground. Thus mitigating signal interference.

Gentlemen, All good sound advise ( no Pun intended)
I like the idea of the walkman!!!
So on the way home fron eastern washington I stopped at Car toys ( local car audio chain) and picked up a ground loop isolator, $20. it solved my problem..... but I had to craink up the volume to get enough output signal to hear the radio. So... this leads me to the ground loop feedback issue. I went nuts grounding and regrounding all the chasis and connections, it did make a difference, slight buzz instead of huge buzz. I know it is a ground loop problem, I ran out of time but will tackle it a bit tomorrow. I will free wire a ground directly to my battery to see if that leads me in the right direction. I need to go thru all the chasis grounds and remake the connections. If this dosn't work I will take Elliotts advise throw the radio out, and listen to my engine.
BTW in my studying I found a very informitave car audio web site, I have to dig up the link and post it later.
I'll keep you posted

I had the same problem, removed all 8 spark plugs and took care of it

Good one I did think of doing that!!

Here is the link to Basic Car audio electronics, very informative site for the DIY'er
http://www.bcae1.com/