I just figured out my Ostrich is giving out a lot of electro magnetic interference. I tested it by using a portable radio and headphones. Whenever I key over and the fuel pump primes, my car radio signal is terrible. I know I could just burn a chip and my problem would be fixed, but I do not have a chip burner.

What can I do to fix EMI? I tried using foil and antistatic bags - no luck.

 

Put it in a lead box???



Does it only interfere with the radio when you're starting the car? Or is this interference there whenever the car is on/running??

What kind of car??

 

What's an Ostrich? Isn't that a bird?

 

its a 2000 civic. I get static the entire time the car is running.
An ostrich is a tuning device which stores your custom map.

here is the website where is is sold.

http://www.moates.net/product_...id=57

 

How does that unit get its power/ground? Is it like a Hondata that gets its power from inside the ECU?

Either way, a bad ground could cause interference...

If you can change the ground of the Ostrich, I'd try that. If it makes no difference, I have no idea.

Have you considered the lead box idea?

 

It gets power from 3 AAA batteries.

 

The small box connects to the ecu by a thin ribbon cable. That may be causing some of the EMI too.

 

A few things come to mind.

You say you key over and when your fuel pump primes you get bad reception.

Your fuel pump should almost always be running. You sure this isn't related to your fuel pump? Have you done anything to it?

It also could just be a bad ground.

Lastly it could be a bad design. These things are usually made pretty cheap. If you can get a schematic you might be able to fix it by properly terminating the transmit and recieve lines. Can you hear it transmit? If you can this a big indicator that the tx and rx lanes are not properly terminated.

What happens is the signal travels down the wire since the load impedence does not match the source impedence some of the signal bounce back and disapates as heat in the source, this is the source of most EMI interference in high speed switching devices. Those wires end upacting like antennas broadcasting noise.

 

I dont understand much of what you said. I do know my fuel pump is not causing this and is not related.

Is there a way to insulated the ribbon cable and plastic box? I have read they make a spray that can help. I was thinking about trying copper spray.

 

Check out these links:

http://www.google.com/search?n...rence

Also, you might try grounding that unit. Is the enclosure plastic or metal?

 

its a plastic unit. Its powered by 3 AAA batteries. Is there a way to power it by my car battery for a better ground?

 

You could definitely crack that unit open and desolder the battery wires from the board, and attach the output from a 12v-4.5v converter in their place...

You'd need a universal cig lighter plug (one that has a variable output from 1.5-12v).

You'd have to attach your input power to the converter where the cig lighter contacts would go, then wire the 4.5v output to the Ostrich.

A little work for a result which I have no idea if it'll correct your problem, but it's worth a shot.

 

Looking at the website I would say the AAA battery is just for memory. Which means it does not supply power to the device. My guess would be power and ground is being supplied through the ribbon cable.

Your EMI interference is probably being transmitted right down the ribbon cable into the power and ground lines. Caused by poor termination. About your only option would be to figure out which pins are power and ground and place a common mode choke there.

Since it sounds like you have no idea what your doing it might be best to have someone who does look at it. Or buy a better designed product.

 

Thank you both very much.

I am going to try to isolate the ribbon cable as much as possible. Try different shielding products and shorten the cable.

I also emailed the website to see if they have any solutions.

I will let you know what works.

 

try unplugging the ribbon cable from the Chip socket and plugging it back in. Sometimes it will get a bad connection here. My car wouldn't run, but after unplugging and replugging it back in it was fine :S