Heard/Experianced something today that was strange...

I think it’s the ABS or the lane departure and collision warning .

I’ve heard it too, I occasionally listen to AM talk stations but can’t stomach the commercials so usually hit a podcast .

 

If you are listening to AM radio I suspect the trucks power inverters are interferring with your radio reception. I know as a truck driver that every truck I've driven with a power inverter has terrible AM reception until I turn off the inverter. A power inverter converts 12 volt DC power into 1110v AC power to power devices like microwave, TV, etc. I've also had a Volvo about 10 years ago and the LED marker lights seemed to interfere with AM radio deception. I used to be a big fan of what's called DX-ing or listening to distant AM radio stations.

 

[QUOTE="tscottme, post: 11991251, member: 19119"12 volt DC power into 1110v AC power .[/QUOTE]
Yikes 1110 volts holy zap batman lol

 

It’s kinda like going from Analog Tv to this Digital.
I just have Antenna at home, every time a car goes by the dirt road i live on, tv goes off for a second.

They forced us to go to digital because it was so much better, like Dish every time it rains the darn thing went off.

 

+1 on inverters, plus nearly everything plugged into them. Some of the worst offenders are usb bricks and other charging appliances. LCD flat panel tv's have a similar transformer inside. Nearly all made in China and very dirty RF emitters. They cut production costs by eliminating or reducing shielding that would prevent noise. Nobody usually notices or cares, as nearly all this stuff is intended for home use where it will be spread out over a larger area.

Pro tip: that noise will also scramble a digital tv antenna signal. If your tv picture is turning into digital soup now and then, it may not just be passing traffic blocking signal. Move any chargers as far away as you can from the tv, antenna and cable, and turn off/unplug any not being used.

Pro tip 2: Cheap HDMI video cables can be dirty with RF noise too. Streaming devices, dvd players, game consoles. Trash the HDMI cables they come with, and replace with name brand, well shielded ones. Doesn't hurt to also turn that stuff off and unplug it when not in use.

Most surprising one I seen? The light in my microwave. One day I forgot to turn off the cb when parking. I stow bread and chips inside the microwave. When I opened the door to get a couple slices of bread for a sandwich, the cb went nuts with hash noise. Closed the door and it went away. It must be a dc lamp fed off a crappy transformer.

 

First understand that the radio system (am/fm-cb) in factory trucks are marginal at best, they are setup for a selling point to the customer, nothing else. Worst am/fm radios on the market are usually OEM radios. The antenna system is at best a compromise between cost and performance.

second the truck manufacturers are using components which actually are noisy. The shielding designs of the ecm, body and abs modules are horrible and produces two types of interference - what is called ultrasonic static and the other is called spurious radiation, both can reach up to the fm band and surely wipe out am and cb reception.

So as a truck passes you, it is the fact that you are hearing signals coming from the trucks electrical system itself and it is blocking signals from the am stations because of the noise it creates and because of what I said in my first paragraph.

now not to forget one other thing, internal noise. I have a lot of chargers like the one that came with rand McNally nav units and a few xm radio receivers that were extremely noisy. These were removed and replacements bought that were quiet. These were so noisy that they came over the fm radio when there was a weak signal.