Radio noise frustration!

[mountainpete]

Ok guys and gals... I need to generate some ideas here

I've been battling ignition noise with my Yaesu 8800R ever since I installed it and it's only getting worse (or else I am just totally fed up with dealing with it) . When the truck is running, I get a crack, crack, crack noise on receive only.

The lower the frequency, the worse the noise. When I listen to 133.xx (I like to listen to aircraft sometimes) it is clear with the engine off, riddled with noise with it on. On 147.xx it is only decent if the repeater is strong. When the truck is off it is crystal clear.

You can see my install here: http://www.expeditionportal.com/forum/showthread.php?t=3044

Over the past year I have tried ferrite everywhere, a Kenwood power filter, etc. But today I tried some new tactics - all leaving me more frustrated!

1 - I powered the radio off of a completely different battery not installed on the truck. Still get the noise. This leads me to believe it's not coming through the power lines, but possibly antenna.

2 - I power the radio off the main truck battery with a different antenna (mag in the middle of the roof) - still get the noise. This tells me it's not the antenna, but probably power.

3 - I power the radio off non-installed battery with the mag mount - still gets the noise! So it's not antenna or power.

4 - So I pull the entire radio, put it on the floor 8 feet away from the truck powered by a battery not installed on the truck. I place the antenna on the truck - noise! So then I pull it off the truck and walk around it. The entire truck must be radiating RF!

This is really frustrating me now. There must be something really simple or stupid leaking RF now. I'm thinking it could either be my alarm system (which I was planning on replacing anyways) or something like plugs/wires.

What do you think? Where would you look next? Are my tests even worthy?

Pete

 

[teotwaki]

Did you notice if the noise seemed to be at all tied into engine RPM?

I would bet it is plugs and wires. The first radio transmitters used spark gaps and they generated VERY broad band noise spectrums.

Take a look here http://www.k0bg.com/noiseid.html
for some great ideas.

 

[mountainpete]

Did you notice if the noise seemed to be at all tied into engine RPM?

I would bet it is plugs and wires. The first radio transmitters used spark gaps and they generated VERY broad band noise spectrums.

Take a look here http://www.k0bg.com/noiseid.html for some great ideas.

Higher the engine RPM, the louder the noise.

I'll take a look at that site - thanks!

 

[teotwaki]

because the install is in your Tacoma I would guess that something has broken such as a grounding straps or gone bad in the ignition setup such as cracked ignition components or wires. Not bad enough to hurt performance/MPGs but enough to generate noise.

 

[mountainpete]

because the install is in your Tacoma I would guess that something has broken such as a grounding straps or gone bad in the ignition setup such as cracked ignition components or wires. Not bad enough to hurt performance/MPGs but enough to generate noise.

Any suggestions on which grounds traps or components to look at first?

 

[AndrewP]

I'd get some ground braid and ground everything. Motor to frame, body to frame, bed to frame. Maybe replace the plug wires if they are not new.

Are you sure it isn't the radio? Try it in another vehicle.

 

[mountainpete]

Are you sure it isn't the radio? Try it in another vehicle.

I think I'm going to hook it up to my Audi and see how it does there.

 

[teotwaki]

I'd get some ground braid and ground everything. Motor to frame, body to frame, bed to frame. Maybe replace the plug wires if they are not new.

Are you sure it isn't the radio? Try it in another vehicle.

On my Bronco I had a similar problem so I waited until it was dark outside and then watched under the hood until I spotted where the spark was arcing to ground. It turns out that a wire had been slightly rubbing against metal and thinned the insulation enough to let the spark escape.

 

[gary in ohio]

1 - I powered the radio off of a completely different battery not installed on the truck. Still get the noise. This leads me to believe it's not coming through the power lines, but possibly antenna.

2 - I power the radio off the main truck battery with a different antenna (mag in the middle of the roof) - still get the noise. This tells me it's not the antenna, but probably power.

The noise is coming in via the antenna. What antenna you use wouldn't matter, where its located may not matter.

4 - So I pull the entire radio, put it on the floor 8 feet away from the truck powered by a battery not installed on the truck. I place the antenna on the truck - noise! So then I pull it off the truck and walk around it. The entire truck must be radiating RF!

Now lets see if we can figure out where its coming from specifically.
Does the noise start when the ignition key is switched on without starting the vehicle. If so that may indicate a fuel pump or control computer.

How stock is your vehicle? what have you added? DO you have a handheld? If so take the antenna off and walk around the vehicle sniffing for RF. Since the signal seems so strong it shouldnt be hard to find. Do you hear any noise on your car stereo on am or fm?

 

[mountainpete]

Now lets see if we can figure out where its coming from specifically.
Does the noise start when the ignition key is switched on without starting the vehicle. If so that may indicate a fuel pump or control computer.

No noise when when the ignition key is on without the engine running. I as thinking fuel pump too so I tried listening for something when the key was on ACC and there is nothing. It only happens when the engine is actually running.

How stock is your vehicle? what have you added?

Far from stock... but electrically almost everything except the remote starter/alarm, lights and the blue sea fuse block has been removed as part of the tests.

As far as other mods, I really need to start that thread (yes Nic, I know!). Short list: Donahoe front & rear, Deaver 10, ARB Bull Bar, M8000 winch (disconencted and removed), IPF Lights, Demello sliders, Demello Hybrid Rear Bumper, BFG MT 255/85R16, Range Rider Canopy, Yakima Racks, Safari Snorkel, etc... everything else is currently removed from the truck.

DO you have a handheld? If so take the antenna off and walk around the vehicle sniffing for RF. Since the signal seems so strong it shouldnt be hard to find. Do you hear any noise on your car stereo on am or fm?

Don't have a handheld VHF. Just thinking, but could it be done with an FRS? I have one that can manually squelch (one of the old ones).

And YES I do get a similar noise when I tune the AM radio an open frequency. The more I rev the engine, the louder the noise is.

Pete

 

[teotwaki]

Put your radio on a small battery to make it "portable". If you have a short length of coax with a connector only on one end you can use that as a shielded probe to sniff for the possible source.

 

[Grim Reaper]

I know on my Toy there is modules in the dash near where the head is. Put the head back on the main unit and see if it clears. That will either eliminate the noise coming off the head or off the RF cable.

If it is still there with the head moved try a different antenna temp erarialy screwed in and tossed on the roof and again. Try to eliminate the antenna being the problem. If its still there then its on the power and it may be a problem wit the unit. Contact the manufacture and explain what you have done to eliminate sources.

 

[p1michaud]

Noisy radio.

Pete,
I'm going to watch this thread very closely. As and FYI, I've got a Cobra CB installed in my Tacoma and have the very same problem. With the truck off, the problem goes away, with the truck running it's awful.
I wonder if the other guys with Tacoma's and 2m installed have had this issue.
Where did they run their power wires and coax?

As far as other mods, I really need to start that thread (yes Nic, I know!). Short list: Donahoe front & rear, Deaver 10, ARB Bull Bar, M8000 winch (disconencted and removed), IPF Lights, Demello sliders, Demello Hybrid Rear Bumper, BFG MT 255/85R16, Range Rider Canopy, Yakima Racks, Safari Snorkel, etc... everything else is currently removed from the truck.

Yes, you do have to get to this ASAP! :shakin:

Cheers :beer:,
P

 

[4RunAmok]

Have you guys tried these?

http://www.powerwerx.com/product.asp?ProdID=1852&CtgID=1003

 

[mountainpete]

I know on my Toy there is modules in the dash near where the head is. Put the head back on the main unit and see if it clears. That will either eliminate the noise coming off the head or off the RF cable.

Tried it Grim - didn't help.

If it is still there with the head moved try a different antenna temp erarialy screwed in and tossed on the roof and again. Try to eliminate the antenna being the problem. If its still there then its on the power and it may be a problem wit the unit. Contact the manufacture and explain what you have done to eliminate sources.

Tried two different antennas, one dual band one single 2m. Tried both antennas on the fender and both in a variety of places on the roof with the mag mount. No difference.