Alternator Noise In Stratus Radio. The Noise Seems To Be Related To The Aux. Power Source.

the other bob

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HecticArt...now I remember ... I installed the Becker/aux. setup back in august 2012. Before that install I had the siri running the fm direct (an optional part not included in the strtus installation box.) with the same power source. There wasn't a noticeable alternator noise at that time. So, that may point in the direction of the audio cable and plug from Becker radio. Thanks for the help. took a while for me to remember lol.....
 

the other bob

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well... today shipped the Becker cdr 24 back to Becker Autosound in New Jersey. They will check their work and the audio cable and aux plug. I will not see it for a few weeks... have a great new year....... bob
 
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the other bob

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It has been a long fruitless journey.... I sent my CDR24 back to Becker Autosound twice..... I still have the alternator noise when engine running. I used an I phone and played it through the CDR aux setup. just plugged it into the jack only, no other power, and it played great............ This suggest that the power of the Porsche CDR radio and the power being supplied to the Sirius radio from the cigarette source create the problem......... Initially the Becker tec said he would find me a ground loop solution for the power or a filter for the power source, however after giving them 2 weeks they say they cant find a solution for the power source and that ends their commitment... so, I'm now on my own to try to find a solution...... any ideas????? bob
 

HecticArt

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Is there another power source you can test?
I don't know how Porsche runs the sources/switching to their fuse blocks.
Can you find a circuit to test that might not be switched just to see if there is a difference?
 

the other bob

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Hello.... I have used both power sources that are present, foot well and arm rest....... I asked a Porsche tec if it was ok to find a "hot" wire somewhere else and was immediately shut down......thank you.....bob
 

the other bob

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I really believe that the interference is the car radio power and the Sirius radio power conflicting ...So..... in other words it is not the source per say, its the very fact that they both exist... Perhaps not related but as example.... Sirius radio when installed with the antenna assist method. You have to dial the car radio to a radio station. As you drive out of that station and into a stronger station on the same frequency, you will get a bleed of the broadcast station on the Sirius radio............. It is funny .... I know I don't know any thing ......but..... I bet that the solution wound be something that I would plug into my Porsches power supply (cig. lighter) and then plug the power (male plug) for the power to the Sirius radio into that....... bob
 

the other bob

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Another way to look at it........ Sirius works by broadcasting its signals though the host radio...... With the engine running, The engine is being broadcast though as well..... bob
 

HecticArt

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I've used the FM transmitter before, and it works ok, but is subjet to what I call "reverse station drift." As you drive around and an FM station that's close to the one you're using gets stronger/clearer, it interrupts the signal your sat dock is broadcasting to your tuner. (Thank the FCC for lowering the power that SXM was allowed to use for their in car transmissions.) Direct line in is better since you don't have to deal with FM drift.

It sounds like there's a neutral/ground, polarity kind of a thing going on between the cars power and the satellites set-up. Since Porche is forbidding you from tapping into the fuse block directly, it's hard to know for sure. Getting to a different power source than a cigarette lighter could answer some questions. Half of the fun of installing a radio yourself is figuring things out and working through the details, but this may be a situation where you need to have a professional help you with the install.

Sent from Tapatalk
 

the other bob

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Yes Tapatalk..... The FM Transmitter system worked better years ago.......... I'm Fred Flintstone when it comes to electrical..... I installed an entire wiring harness in my Porsche Roadster. And removed a complete wiring harness from a 1967 9/11 and installed that in my 1966 9/12. Both cars work perfectly. My procedures are those of testing by comparison to a toaster. If it could make toast ....I was wrong.....So.... this methodology wont work on the Boxster..I have to treat this car as a plug and play computer.....I will have to know the correct protocol before proceeding. I would feel safe installing a device in the Porsche aux power plug (cig. lighter) that was designed for that port...... I have tested the waters on finding a pro shop to tackle the problem and the response was not encouraging.... I may have to push it harder.... Thank You.....
One last dumb question............The power plugs that you push into the cig. lighter are shielded to filter interference ...so I was told..... I wonder if putting two of these in line would filter down the interference........ bob.
 

Casual Fan

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These kinds of questions were easier back in the day when everybody and their uncle were doing Sirius car installs. Now, almost no one does a car install, and instead uses the AUX port to stream from their phone or something.

Have you tried a car stereo forum or Porsche forum? Because those guys are definitely familiar with your car's electrical system. There's just too little traffic on installs nowadays on forums like this. I mean, we used to have (on our old legacy forum, Sirius Backstage) daily photo spreads of installs. No longer.
 

the other bob

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That's a great suggestion..... I may not of tried enough Porsche forums.... I will be limited because the setup I have requires the person to remove the Becker CDR and send it to Becker for modification ..... How many owners have done that?.......... It's clear that the Becker modification works great with I phone etc.... Thanks all for the support. I wont give up........ I'm sure there is a solution............ bob
 
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the other bob

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Well ...Well... Well.... I searched the backstage archive and found a person with the exact same phenomena. A 2005 Boxster with the factory Becker CDR and the Becker Aux Audio "kit". The exact "symptoms" . And he expresses that it is fixed. He used a ground loop isolator. Only problem.... I don't understand what he says /or were he is putting it, because the isolator linked to the story has R/C jacks and I have know Idea in my system were this would go.
 
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the other bob

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I just wanted to close the issue. Yes, it worked.
It looks like mine was an inductance issue on the rca cables. If they go ANYWHERE near the single din space the h2a is in, they generate alternator whine. My guess is there is something else back there that pumps out a good amount of noise.
Here is the story: Went to circuit city and purchased a ground loop eliminator. Got home and pulled the radio and the H2A to expose all of my wiring. Hooked up the ground loop elim between the h2a and the radio, but it kept on humming. I was resigned to just disconnecting it and bringing it back when I put the eliminator on the din shelf where the radio normally goes, when the sound went away. I disconnected it, rerouted the wires, plugged it back in and shoved it behind the radio. Works fantastic now.
So now everythign sounds great, but I experience tons of dropouts due to the antenna placement... Being as I have a boxster, there are only a few places you can put the antenna on the outside, and none of them look good. So I just got some heavy duty velcro, put it on the top of the antenna, and attached it to the underside of the plastic waterrunoff tray between the hood and the windshield. (Look at your car for the plastic between the windshield and hood, thats what I am talking about.
It is surrounded by metal surfaces, but it does not rest on the metal itself.
Fully hidden antenna install and it works great. No dropouts except under a few long bridges.
 
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the other bob

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The last above post was the other Boxster owners description of how he installed the isolator..... Can anyone express this in flinstoneese.......... bob
 

the other bob

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Yes... this is the post on Sirius Backstage....I just wanted to close the issue. Yes, it worked.
It looks like mine was an inductance issue on the rca cables. If they go ANYWHERE near the single din space the h2a is in, they generate alternator whine. My guess is there is something else back there that pumps out a good amount of noise.
Here is the story: Went to circuit city and purchased a ground loop eliminator. Got home and pulled the radio and the H2A to expose all of my wiring. Hooked up the ground loop elim between the h2a and the radio, but it kept on humming. I was resigned to just disconnecting it and bringing it back when I put the eliminator on the din shelf where the radio normally goes, when the sound went away. I disconnected it, rerouted the wires, plugged it back in and shoved it behind the radio. Works fantastic now.
So now everythign sounds great, but I experience tons of dropouts due to the antenna placement... Being as I have a boxster, there are only a few places you can put the antenna on the outside, and none of them look good. So I just got some heavy duty velcro, put it on the top of the antenna, and attached it to the underside of the plastic waterrunoff tray between the hood and the windshield. (Look at your car for the plastic between the windshield and hood, thats what I am talking about.
It is surrounded by metal surfaces, but it does not rest on the metal itself.
Fully hidden antenna install and it works great. No dropouts except under a few long bridges. ....that's it HecticArt