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Discussion Starter · #1 ·
Can anyone provide a simple diagram and parts list for the electrical components to build a noise isolator?

When I have my phone plugged in to the LT's 12v system, I get an incredible amount of electrical noise.

I seem to recall one or more of you building an isolator to filter out the power line noise, and I would appreciate any assistance.
 

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"What" exactly do you have plugged into the LT's electrical system and where? This is highly unusual and probably indicates a bad power connector, poor grounding, and/or poor conductor sheilding of the audio portion of the connector. Normally, isolators are not needed.
 

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Discussion Starter · #3 · (Edited)
Whether iPod, iPhone, blackberry, or android phone, if plugged into 12v socket and connected to Autocom input, there is interference. If the input device is running off its battery, no problem.

This occurs whether the device is plugged into any of the factory power ports or into the conventional 12v socket I installed using quality 14ga stranded copper run directly to the battery terminals.

I respectfully disagree, this is not highly unusual and is not an isolated problem (UN-intentional pun). I have seen multiple threads about it here over the years, and the resolution, IIRC, was to isolate the power to the device.
 

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Got to agree with Tony on this one.

My 09 does the same thing with my Droid Razr. It's blue tooth to the gps and on it's own battery and I still can't talk out. If the engine is at idle or off it's perfect. Soon as I go above idle massive interference.

Tried plugging in to the phone port on the Voice 2 but same problem.

Tried a ground loop isolator in the line from the gps to the voice 2 aux plug but no change.

Tried my wife's phone (same model) and her helmet in place of mine also.
 

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Discussion Starter · #5 ·
kevincaron said:
Got to agree with Tony on this one.

My 09 does the same thing with my Droid Razr. It's blue tooth to the gps and on it's own battery and I still can't talk out. If the engine is at idle or off it's perfect. Soon as I go above idle massive interference.

Tried plugging in to the phone port on the Voice 2 but same problem.

Tried a ground loop isolator in the line from the gps to the voice 2 aux plug but no change.

Tried my wife's phone (same model) and her helmet in place of mine also.
Was my thinking that a ground loop isolator would solve the noise issue, and that is what I was asking for a circuit layout for.

I suppose another possibility is an alternator noise filter, but the noise I get does not seem to be typical alternator whine.
 

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deputy5211 said:
Whether iPod, iPhone, blackberry, or android phone, if plugged into 12v socket and connected to Autocom input, there is interference. If the input device is running off its battery, no problem.

This occurs whether the device is plugged into any of the factory power ports or into the conventional 12v socket I installed using quality 14ga stranded copper run directly to the battery terminals.

I respectfully disagree, this is not highly unusual and is not an isolated problem (UN-intentional pun). I have seen multiple threads about it here over the years, and the resolution, IIRC, was to isolate the power to the device.
No disrespect intended, but I have extensive experience building and installing car stereos. I also just installed a Jensen JMS2212 in my 2005LT. From my experience, I can tell you there is most likely a problem with one or more of the following:

1. Audio wiring (Line in, output) not separated from DC power wiring and/or insufficient shielding of such audio wiring. Ideally, all audio wiring with the Autocom system should be routed away as far from the engine electronics as possible. Also, if the sheilding is not properly bonded through its connector and to the bike's chassis ground, it will act like an antenna and pick up the ignition ticks or the alternator AC whine. See #2.

2. You might have a ground loop issue. This means that some grounding points on your engine/frame/harness have different potentials. This is likely caused by a loose connection, corrosion, or improper bonding of systems. Ideally, all ground attachment points will have the same exact potential. I would check (remove, clean, inspect) all primary grounding points on your LT. (See Clymer manual for detailed grounding locations).

The Autocom units have had problems with being wired incorrectly. Please see here to confirm if yours has been wired properly:

http://autocomdirect.com/pdf/CarTypeMusic.pdf

Also, there have been a few threads which addressed this issue: Here

Here

Here

Many people already have an Autocom system installed with no such problem. Before you go crazy purchasing and installing random power isolators, which may not solve your issue, please read through all the threads first. If you have, I apologize.

You may need a specific Autocom Audio isolator module depending on your combination of actual devices and how they are powered (internally or externally by bike). They have these defined on their website at: Here

Good Luck!
 

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Discussion Starter · #7 ·
Looks like I have some reading to do. Thanks for the awesome references!

Will post next after I digest it all.
 

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Tony I originally had an issue with my 2720 and the Autocomm and solved it with an isolation transformer on the audio in. But I have been running a Driod X in the car dock right into port 2 on my Autocomm with no issues ( I do hear the Droids computer noise faintly). Also my Zumo 660 is wired direct with no transformer and no noise issues. There is hope!
 
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