Interference (cell phone charger)

[Saint]

I thought I would post a screen capture of the interference on my waterfall from my Samsung S9 when it's charging. I am using a SDRplay RSPdx and SDRuno software. Everything on the waterfall is interference from the charger except the signal at the far write of the screen that's a fax signal coming in. As soon as I take my cell phone off the charger all the waterfall clears up.
Steve

 

[RFI-EMI-GUY]

Wonderful. Those chargers are everywhere now polluting the airwaves.

 

[mmckenna]

My son had a 12 volt - USB charger that would take out the tire pressure monitoring system in our old car. Took me a while to figure it out.
Smashed it with a hammer so it wouldn't get pulled out of the trash and bother me again.
Replacement charger never caused that issue.

 

[sonm10]

I've had this question for quite some time, how do you "clean up" a noisy USB? Would a USB isolator work? What is a source of clean 5 volts?

 

[KX0Z]

Probably cheap noisy Chinese circuitry. I had a charger that would almost wipe FM radio stations in my car. Junked that POS

 

[mmckenna]

I've had this question for quite some time, how do you "clean up" a noisy USB? Would a USB isolator work? What is a source of clean 5 volts?

Easy, you use a BFH.

Big Flippin' Hammer. You beat the device until it resembles powder. Then you beat it some more.

The issue is internal. Cheap components. Can take trial and error to find a good one, but name brand stuff is usually pretty good.

 

[RFI-EMI-GUY]

I am on a couple car related groups and folks with new cars are complaining about key fobs not working, tire pressure sensors not working. This probably explains it.

I think I read somewhere a company that makes USB chargers for airplanes that are low in RFI.

 

[Saint]

I thought I would post a screen capture of the interference on my waterfall from my Samsung S9 when it's charging. I am using a SDRplay RSPdx and SDRuno software. Everything on the waterfall is interference from the charger except the signal at the far write of the screen that's a fax signal coming in. As soon as I take my cell phone off the charger all the waterfall clears up.
Steve

Sorry I should have said what charger I am using. It's a Namami Fast Charger, It stands up my cell phone when charging
She's really doing a job on the waterfall today.
Steve

 

[mmckenna]

I think I read somewhere a company that makes USB chargers for airplanes that are low in RFI.

I'd be interested to know more about that product, if you run across it again.

My case was a USB cigarette lighter plug device my son was using for his Nintendo Switch. We were somewhere near Flagstaff AZ. Tire Pressure light came on. I stopped and checked all 4 tires, no issues. Kept driving for a bit, stopped again, checked, all OK.
Continued on. While driving, I remembered others talking about this issue. I pulled the plug on his charger and within a few minutes, the fault cleared.

 

[Saint]

I'd be interested to know more about that product, if you run across it again.

My case was a USB cigarette lighter plug device my son was using for his Nintendo Switch. We were somewhere near Flagstaff AZ. Tire Pressure light came on. I stopped and checked all 4 tires, no issues. Kept driving for a bit, stopped again, checked, all OK.
Continued on. While driving, I remembered others talking about this issue. I pulled the plug on his charger and within a few minutes, the fault cleared.

Got it off Amazon.ca
Fast Wireless Charger, NANAMI Qi Certified Wireless Charging Stand Compatible iPhone 13/13 Mini/12/12 Pro Max/SE 2/11/11 Pro/XR/XS Max/X/8+,Samsung Galaxy S22 S21 S20 fe S10 S9 S8,Note20/10+,Pixel 6/5

 

[hanlonmi06]

Its amazing how many devices create similar issues. Literally just minutes ago I confirmed my alarm system is spewing out some RFI from the keypad. I've gone as far as getting a plain iron core transformer power supply to send 5v DC to a few spots and hack some usb cords to just do 5v charging. I've also found that power tool battery chargers just love to radiate while not charging, just being plugged in will wipe out entire chunks of spectrum for me.

 

[slicerwizard]

Wireless phone chargers use a ~150 kHz chopper circuit to drive a coil antenna. And what do on/off chopper circuits create? Square waves. And what do square waves consist of? Harmonics. LOTS of harmonics. And you're feeding them to an ANTENNA. And then users wonder why their HF/VHF noise floor is dancing on the ceiling...

 

[Dirk_SDR]

I'm using iDefender:

iDefender+ by iFi audio - Protect against Ground Loop Noise & Noisy USB power

The new Defender of the earth. Multiple plugs and ports produce separate earth points, creating an unwanted chain of buzz and distortion. The iDefender+ plugs into your USB port, can inject super clean 5-volt power and creates a single earth point for faster, cleaner sound quality.

ifi-audio.com

... with a clean 5V supply:

iPower2 by iFi audio - Ultra Low Noise DC Power Supply with international options.

Power up your system. Upgrade your existing power supply to the iFi iPower2 to flood your system with quiet, noise-free audiophile-grade clean power.

ifi-audio.com

 

[Boombox]

I only charge my phone once a week or so, maybe every other week. Same with my tablet computer. If you don't use the devices a lot, your RFI level drops considerably.

 

[dlwtrunked]

Sorry I should have said what charger I am using. It's a Namami Fast Charger, It stands up my cell phone when charging
She's really doing a job on the waterfall today.
Steve

And you should tell us what receive antenna (and where)?

 

[Saint]

And you should tell us what receive antenna (and where)?

Fort Erie Ont.
SDRplay RSPdx
SDRuno Software 1.41.1.
MFJ 1886TR LOOP Antenna
Also all this info is in the bottom of all my posts
Steve

 

[slicerwizard]

Pretty sure he means where is the antenna relative to other stuff (like the charger)

 

[Saint]

Pretty sure he means where is the antenna relative to other stuff (like the charger)

The Antenna is outside on my 4th floor Balcony

Approximately 30' away from my charger

 

[mmckenna]

The noise can be from the charger itself, radiated by the USB cord, radiated into the 120vac wiring, radiated from the device.

The scanner can pick it up via the power supply, via the antenna, or leaking through the plastic parts of the case.

 

[dlwtrunked]

Fort Erie Ont.
SDRplay RSPdx
SDRuno Software 1.41.1.
MFJ 1886TR LOOP Antenna
Also all this info is in the bottom of all my posts
Steve

Not the loops antenna location (where?)--how far away from wiring, etc.