BC780XLT: "Interference"

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FIREBOX2914

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Couldn't find an answer to my issue.

I have a 780XLt in my car and power it using the cigarette lighter. Whenever I try to charge my phone (via the other power port or a external power pack) I get interference to the point i dont even pick up the transmissions when im sitting half mile away.

Is their someway to cut the interference??

I use the 780 for VHF/UHF MilAir mainly.

Thanks
 

mancow

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Not much you can do really. Maybe try some snap on ferrite beads but I find that it's difficult to mitigate.
 

k0aa

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Couldn't find an answer to my issue.

I have a 780XLt in my car and power it using the cigarette lighter. Whenever I try to charge my phone (via the other power port or a external power pack) I get interference to the point i dont even pick up the transmissions when im sitting half mile away.

Is their someway to cut the interference??

I use the 780 for VHF/UHF MilAir mainly.

Thanks
The only way I know to address the problem is to install a pair of fuse-protected DC power conductors from the battery to the scanner. Many cigarette lighter circuits share the same conductors that supply 13.8 VDC to other components.

Cigarette lighter sockets work well for lights and cell phone charging. However, I don't feel they are suitable for supplying DC power to AM receivers. Sometimes, they will allow reception of FM without receiving noise. Because VHF and UHF aircraft channels are 98% AM, noise superimposed on the power to your 780xlt ruins your reception.

As you know, the 780xlt scanner is an ideal aircraft receiver. Best wishes.

Sent from my HTC One M9 using Tapatalk
 

jonwienke

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The 12V-to-USB adapter you're using to charge your phone is the problem. It's generating RF interference. If you can replace it, do so.

Another option is putting something like this on your scanner power supply:
https://www.amazon.com/Magnum-XLF-20BP-Common-Power-Filter/dp/B01IC27LHW

Also, try coiling all of your antenna's spare coax into a loop about 4" in diameter to make a common-mode filter that may reduce the pickup of RFI coming from inside the vehicle.
 

DJ11DLN

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I once had a car phone charger that behaved that way; it would create so much RF noise that it would basically choke out any and all traffic on the scanner, period. Switching to a USB lighter plug and using the cord from the house charger solved the problem. Simple bad circuitry in the mobile phone charger. It had an FCC certification sticker on it...I wonder if it got "rubber stamped" or if anybody actually checked to see if it was generating "harmful interference?" Sad state of affairs indeed when we have to figure out ways of charging our one sort of mobile devices without generating enough interference to render our other mobile devices useless.:roll:
 

jackj

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Welcome to the wonderful world of switched power supplies. They are cheap to build, efficient and light weight --- BUT --- if the manufacturer cuts corners then they are also very efficient white noise generators. There isn't any way to judge their noise output short of using them. They're in everything now, CFLs, TVs, even clocks. There are ways to filter the output and remove the noise before it leaves the device but they cost money so a lot of the stuff made in China doesn't have the filters. Trial-'n-error is about the only thing you can do.
 

FIREBOX2914

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The 12V-to-USB adapter you're using to charge your phone is the problem. It's generating RF interference. If you can replace it, do so.

Another option is putting something like this on your scanner power supply:
https://www.amazon.com/Magnum-XLF-20BP-Common-Power-Filter/dp/B01IC27LHW

Also, try coiling all of your antenna's spare coax into a loop about 4" in diameter to make a common-mode filter that may reduce the pickup of RFI coming from inside the vehicle.
The antenna is hooked right to the scanner its the stock extendable/collapsible one.

Oddly enough Im using a USB/Cigarette Lighter plug to charge. Guess ill play some trial & error.
 

jonwienke

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The antenna is hooked right to the scanner its the stock extendable/collapsible one.
In a vehicle, this is recipe for disaster. Get an antenna outside the vehicle or you're going to be endlessly frustrated.
 
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