RF Interference from Amcrest cameras

I

insanity213

n3wb
Oct 3, 2016
6
0
Need some help with an RFI problem. I have 6 Amcrest ProHD Outdoor 1080P POE Security Bullet Cameras on my property. It doesn't matter if I power them directly with a 12v PSU or via PoE, the camera itself lets out a whole lot of RF noise. It is slightly worse when powered via PoE but even when powered locally via an RF quiet 12v PSU, the Ethernet cable turns into an antenna for all of the noise generated by the camera. I put some ferrite beads on the Ethernet cable but it didn't make any difference. With just a single camera running it causes pretty bad problems across the 2 meter ham radio band (144-148mhz). On a few frequencies (146.510 seems to be the worst) the noise is even full quieting and sounds like a radio that forgot to stop transmitting. With all 6 of these things powered up the 2 meter band is pretty much unusable except for the most powerful transmitters and even then the transmission is quite noisy. Some quick checks also lead me to believe it's throwing RF spurs at random spots in the HF bands (3 to 30mhz) but I'll have to do some more testing before I swear to that statement. I don't have any gear to check between the mid VHF frequencies and UHF but the noise is not present in the low UHF Frequencies (380mhz up to 480mhz).

Even if I threw dedicated clean PSU's at each camera and use shielded twisted pair the noise will still emanate from the case of the camera itself as well as get thrown back into whatever Ethernet switch I use to aggregate the cameras. I'm willing to bet this is why my smart garage door opener has a mind of its own too.

Has anyone here run into something like this before and come up with a solution that didn't cost more than the cameras did?

Can anyone recommend a 1080p Ethernet based camera that is quiet from an RF emission standpoint - especially in the HF and VHF bands?

Amcrest claims to have FCC certifications for these devices, but if they are emitting a full quieting signal on licensed spectrum there's not an ice cubes chance the device is really part 15 compliant. I wonder if they'll buy them back?

Any words of wisdom would be appreciated!
 
There's a lot of non-compliant category cable out there, i'd be curious what a bench test yields with a short known good cable.
STP may do more good than you realize.
Try a different switch or no switch and directly connect a single camera to a computer just to rule out the switch as a source of interference. Or simply power the camera with no network cable connected.
Ferrite beads have to be carefully chosen to do much good.

A better camera may be less of an issue. I don't think @nayr has had any interference issues from his higher quality dahua cameras on his ham.
 
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What the model number of these cams? Do they have wifi?

Some amcrest cameras are crappy foSCAM rebrands others are low end Dahua rebrands.
 
I have checked the camera just powered by a 12 volt known good psu with no cable conneted and the camera itself is most certainly the source of the RFI. I've tried several known good 5e and 6 cables. The RFI is just so powerful that it doesn't matter how twisted the cable is, noise comes blasting out of it.

I want to say it's one of the rebranded foscams... Whichever ones they were selling at Microcenter for 79 bucks. Not wifi or anything, hard wired only.

Sent from my Pixel XL using Tapatalk
 
Presumably the camera doesn't have a grounded metal case.
if not, maybe try giving it a tinfoil hat.
Sounds like a silly idea - but in combination with the shielded ethernet cable it might just help.
 
Best option is probably to sell the cameras or return them if you can. I'd have low expectations of Amcrest being concerned. Is there a way to file a report with the FCC?
 
Yeah, I could probably file an FCC report but wonder how much they'll really care. Unfortunately I've had the cameras for about a year now so I'll probably be stuck with them.

Any idea what cameras I might have better luck with?

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And the cameras are aluminum cased, maybe ill try firing one up on a test bench and running a ground from the chassis of the camera to the 3rd lug of an outlet and see if it improves.

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Just curious, how did you discover this problem ?

I don't know how this camera convert incoming 12V down to the Voltage really needed on the PCB but if it use DC-Bucks instead of linear converter they are known to be noisy and should be shielded but they work in a range of 150-300Khz not Mhz.

Can you test changing camera's resolution down to 720P just to see if it changes something to this noise ?

But anyway if you just bought them...send them back to vendor and refund !
 
Wish I could send them back but I've had them about a year. I've only had my ham ticket since December so I've just begun to realize what an RF cesspool my house is. I don't think changing the video settings will make a difference being that the noise is present with or without a network connection but will try it just for the sake of testing.

I have one camera that Ive yet to permanently install that will be my guinnea pig this weekend.

Sent from my Pixel XL using Tapatalk
 
insanity213 said:
(146.510 seems to be the worst)
Click to expand...
That may be the master oscillator / clock source. It's likely the CPU clock is going to run at a multiple of that with an internal multiplier.
I'm not familiar with that specific camera, but extrapolating from similar Hikvisions, on older cameras the CPU clock is around 500MHz, on newer ones around 1200MHz.
 
insanity213 said:
I have checked the camera just powered by a 12 volt known good psu with no cable conneted and the camera itself is most certainly the source of the RFI. I've tried several known good 5e and 6 cables. The RFI is just so powerful that it doesn't matter how twisted the cable is, noise comes blasting out of it.

I want to say it's one of the rebranded foscams... Whichever ones they were selling at Microcenter for 79 bucks. Not wifi or anything, hard wired only.

Sent from my Pixel XL using Tapatalk
Click to expand...
Couple years ago I stuck one of my brothers foscams above my garage door. My garage door opener wouldn't work unless I was 5 feet away, as opposed to 50 feet normally. Didn't matter if it was wi-fi or ethernet as soon as I unplugged power it would go away. I've had three Dahuas above the door for a year and everything's fine.
 
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Just scanned 2 meters with a Yaesu VX-5 next to a Dahua 5231 turret (see Tangent's link above) and all was quiet.

73 OM
 
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