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#41364 - 11/10/2001 10:43 Interesting Issue....
declain
journeyman

Registered: 30/08/2001
Posts: 68
Loc: Massachusetts, USA
I happen to be an EMT (on top of being a geek), and just installed a scanner (radio frequencies) into my car right above the Empeg. I have a Toyota Solara, with the empeg and scanner both in the double din (tight fit, but barely worked). The Empeg sits on the bottom and the scanner right above it.

So, here's the issue I am having. The Empeg works fine. The scanner, when tested (on the passenger seat, outside the dash), worked fine. It is using an 18" whip antenna mounted on the trunk. Now, when I moved the scanner into the dash, the ability for the scanner to pick up signal was greatly reduced, by near to 50%.

I moved the tuner module so that it is now as far away from the scanner as possible, but it does not seem to help. It could have to do with the empeg sled, but that should be grounded through the normal wiring.

So, does anyone have any suggestions? I would rather not move the scanner out of the dash, as there is not much room in the front of the car for it. Not to mention the perfect fit in the dash (I will post pictures in the near future of the install).

Any suggestions would be appreciated. I am wondering if it is the sled not being properly grounded or maybe signal spill from the tuner module???? Before ripping it apart again, thought I'd try here....

//== MK2 20 GB Single Drive, Green Face Plate Currently installed in Toyota Solara ==\\
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//== MK2 Rio Car 20 GB Single Drive ==\\

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#41365 - 11/10/2001 11:08 Re: Interesting Issue.... [Re: declain]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
First, rule out the car itself by having everything installed but the empeg pulled out of the sled. Get the car engine running and see if the scanner works acceptably in the dash. If it doesn't work, then it's got nothing to do with the empeg, it's the car or the wiring.

(Note, I'm assuming you've got a way to listen to the scanner without the Empeg being in the loop, right? If not, jerry-rig something...)

Then rule out the tuner module by de-installing it completely.

Next, rule out ground loops by disconnecting the RCA cables of various components and seeing if the problem clears up when you do.

Then set the empeg's timeout value to 5 seconds, and set it up so that you can pull its ignition sense wire. With the car running and the scanner listening, pull the ignition sense wire connection to the empeg. The empeg should drop to standby mode. After 5 seconds, it should drop out of standby mode and fully power down.

This will allow you to see the difference between the "empeg on standby" and the "empeg fully off" modes.

If the scanner gets better when the empeg goes into standby, then you've got some kind of crosstalk in your wiring. For instance, maybe your scanner antenna runs along next to your amplifier power cable.

If the scanner gets better when the empeg goes into full power-off mode, then it's RF interference from the empeg's CPU, electronics, and/or hard disks. Note that the empeg passes FCC regulations for a car stereo, so it's "within spec" and there's nothing that can be done about it. However you could work around it by leaving the empeg's timeout really short and figuring out a way to shut it off when you use the scanner.

Maybe it's something as simple as changing the order of the items in the dash (put the OTHER unit on top instead of the bottom). Perhaps that would be enough to change the RF fields in the dash so that it works acceptably.

___________
Tony Fabris
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Tony Fabris

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#41366 - 11/10/2001 11:40 Re: Interesting Issue.... [Re: tfabris]
declain
journeyman

Registered: 30/08/2001
Posts: 68
Loc: Massachusetts, USA

In reply to:

First, rule out the car itself by having everything installed but the empeg pulled out of the sled. Get the car engine running and see if the scanner works acceptably in the dash. If it doesn't work, then it's got nothing to do with the empeg, it's the car or the wiring.



The scanner worked great when the previous radio was installed. It also work on top of the dash, thus ruling out the car.
In reply to:

Then rule out the tuner module by de-installing it completely.



This was my next move, but being as it is a major pain, I posted to get a second opinion.
In reply to:

Next, rule out ground loops by disconnecting the RCA cables of various components and seeing if the problem clears up when you do.



Definitely not a ground loop issue. All grounds are to a grounding block and when removed all RCA cables, probem is still there.
In reply to:

This will allow you to see the difference between the "empeg on standby" and the "empeg fully off" modes.
If the scanner gets better when the empeg goes into standby, then you've got some kind of crosstalk in your wiring. For instance, maybe your scanner antenna runs along next to your amplifier power cable.
If the scanner gets better when the empeg goes into full power-off mode, then it's RF interference from the empeg's CPU, electronics, and/or hard disks. Note that the empeg passes FCC regulations for a car stereo, so it's "within spec" and there's nothing that can be done about it. However you could work around it by leaving the empeg's timeout really short and figuring out a way to shut it off when you use the scanner.



Maybe I should have added to my original post that this happens when the empeg is fully out of the sled (and in the house). So, I have completely ruled out it being interference from the actual empeg. In addition, I did ran the scanner antenna down the right side of the car, the speaker and rca wire down the middle, and the power down the left. This should minimize or remove any wire interference.
In reply to:

Maybe it's something as simple as changing the order of the items in the dash (put the OTHER unit on top instead of the bottom). Perhaps that would be enough to change the RF fields in the dash so that it works acceptably.



I was thinking about this as well, but will leave as a last resort, as I doubt this is the cause. Although, it might be nice to have the empeg higher in the dash anyway....

The only thing you didn't mention that I haven't tried is removing the sled completely and leaving the tuner module in there. This, in conjunction with the other test, taking the tuner out, would maybe isolate the problem. I just know how much of a pain the sled will be to remove due to some barely long enough speaker wires, but if I am going to have the car apart, I might as well rewire the speakers...

Tony, thanks for the input. It seems you basically confirmed my thoughts on needing to rip the car apart again....Oh well, here goes another Saturday


//== MK2 20 GB Single Drive, Green Face Plate Currently installed in Toyota Solara ==\\
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//== MK2 Rio Car 20 GB Single Drive ==\\

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#41367 - 11/10/2001 12:01 Re: Interesting Issue.... [Re: declain]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
Maybe I should have added to my original post that this happens when the empeg is fully out of the sled (and in the house).

Then you are almost definitely talking about some kind of a wiring problem. Re-check all connections, plugs, and wiring runs. Even the ones you're sure are fine. Check to make sure that no wires have pulled out of their connector plugs or gotten loose.

Can you give us a more detailed wiring description?

___________
Tony Fabris
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Tony Fabris

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#41368 - 11/10/2001 12:35 Re: Interesting Issue.... [Re: tfabris]
declain
journeyman

Registered: 30/08/2001
Posts: 68
Loc: Massachusetts, USA
I will write up a wiring diagram tomorrow and post it. I have my scribbles, but can easily translate. I will also do a double check on the wires, but checked them last night and all were tight, connected, and the non used ones were taped off.

All connections were made with insulated crimp connects.


//== MK2 20 GB Single Drive, Green Face Plate Currently installed in Toyota Solara ==\\
_________________________
//== MK2 Rio Car 20 GB Single Drive ==\\

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#41369 - 11/10/2001 12:46 Re: Interesting Issue.... [Re: declain]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
It also still could be some kind of a ground loop issue with the chassis and antenna connections. Try setting the scanner on the passenger seat and getting it to work right, then connecting/disconnecting a wire between the scanner frame and the dash frame and see if the problem comes and goes.

___________
Tony Fabris
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Tony Fabris

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#41370 - 11/10/2001 13:19 Re: Interesting Issue.... [Re: declain]
rtundo
addict

Registered: 27/02/2001
Posts: 569
Loc: Albany, NY
Does the problem occur when the empeg is turned on? Or does it also occur when the empeg is off? The reason I ask is that the empeg (when on) has been known to effect the range of key lock remotes on some cars. Is it possible this is occuring in the case of your reception?


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#41371 - 11/10/2001 13:42 Re: Interesting Issue.... [Re: rtundo]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
Already covered. Read the rest of the thread. It happens without the empeg anywhere near the car. It's got to be something in the wiring and grounding.

___________
Tony Fabris
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Tony Fabris

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