TV Fool  

Go Back   TV Fool > Over The Air Services > Special Topics

Notices

Reply
 
Thread Tools
Old 26-Jul-2018, 10:35 AM   #1
Bigbear
Member
 
Join Date: Jun 2014
Posts: 53
Interference

I hope this is the correct forum .
I have a pair of TV Ears that broadcast in infra red @ 2.3MHz. Lately when my wife plugs in her laptop power supply it interferes with my TV ears. I swapped out the battery pack on the ears to no avail.
Anyone have ideas on what is going on, or where I can go for answers?
TV ears page is no help.

Thanks
Bear
Bigbear is offline   Reply With Quote
Old 26-Jul-2018, 2:39 PM   #2
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Hello, Bear

The AC adapter for the laptop contains a switchmode power supply (SMPS). That type of power supply is very efficient, but often radiates interference.

It could be causing interference to the TV Ears or to the TV. Does the laptop adapter cause interference to the TV when the TV Ears transmitter is not connected to the TV?
__________________
If you can not measure it, you can not improve it.
Lord Kelvin, 1883
http://www.megalithia.com/elect/aeri...ttpoorman.html
rabbit73 is offline   Reply With Quote
Old 26-Jul-2018, 5:48 PM   #3
Bigbear
Member
 
Join Date: Jun 2014
Posts: 53
No it has no affect on the tv. The interference is a recent thing that with this power supply.
Bigbear is offline   Reply With Quote
Old 26-Jul-2018, 10:05 PM   #4
ADTech
Antennas Direct Tech Supp
 
Join Date: Jan 2010
Posts: 2,942
OEM or aftermarket power supply?
__________________
Antennas Direct Tech Support

For support and recommendations regarding our products, please contact us directly at https://www.antennasdirect.com/customer-service.html

Sorry, I'm not a mod and cannot assist with your site registration.
ADTech is offline   Reply With Quote
Old 27-Jul-2018, 10:59 AM   #5
Bigbear
Member
 
Join Date: Jun 2014
Posts: 53
For the computer? OEM Lenovo
Bigbear is offline   Reply With Quote
Old 27-Jul-2018, 1:17 PM   #6
ADTech
Antennas Direct Tech Supp
 
Join Date: Jan 2010
Posts: 2,942
Hmmm.... Did anything in particular change that was coincidental to the beginning of the interference?


Have you gone in and re-seated any audio patch cords between the TV and the transmitter?
__________________
Antennas Direct Tech Support

For support and recommendations regarding our products, please contact us directly at https://www.antennasdirect.com/customer-service.html

Sorry, I'm not a mod and cannot assist with your site registration.
ADTech is offline   Reply With Quote
Old 27-Jul-2018, 2:10 PM   #7
Bigbear
Member
 
Join Date: Jun 2014
Posts: 53
Don't know what happened.Everything was fine until a few weeks or so. I installed new batteries of the TV ears, dusted the transmitter, and disconnected and re connected all the connections.
Wifey does not have another power supply to see if it's the cause.
Bigbear is offline   Reply With Quote
Old 27-Jul-2018, 2:50 PM   #8
ADTech
Antennas Direct Tech Supp
 
Join Date: Jan 2010
Posts: 2,942
The batteries in the earphone set will not cause this. Because your earphones are infrared from the transmitter, I would not expect them to directly receive the interference from the power supply unless there is a very odd internal failure. I'm more suspicious that the issue is that your transmitter is picking up the noise, either from the power line or via direct radiation.

Does the same interference occur if the laptop power supply is plugged into a receptacle on a different branch circuit served by, usually in a different room?

Is it sensitive to changes in distance or orientation between the power supply and the transmitter.

Trying to determine if the issue is due to conducted radiation (via the home's wiring) or is radiated directly from the power supply to your transmitter or its wiring.
__________________
Antennas Direct Tech Support

For support and recommendations regarding our products, please contact us directly at https://www.antennasdirect.com/customer-service.html

Sorry, I'm not a mod and cannot assist with your site registration.

Last edited by ADTech; 27-Jul-2018 at 2:55 PM.
ADTech is offline   Reply With Quote
Old 27-Jul-2018, 3:31 PM   #9
Bigbear
Member
 
Join Date: Jun 2014
Posts: 53
Maybe conducted as it occurs to a lesser extent when plugged in another room. Or not as when in another room the interference seems less and directional. That is I get the interference changes with the orientation of the TV ears.
Wonder if I could put a Faraday cage around the power supply!
Bigbear is offline   Reply With Quote
Old 27-Jul-2018, 5:51 PM   #10
ADTech
Antennas Direct Tech Supp
 
Join Date: Jan 2010
Posts: 2,942
Try wrapping it with aluminum foil.
__________________
Antennas Direct Tech Support

For support and recommendations regarding our products, please contact us directly at https://www.antennasdirect.com/customer-service.html

Sorry, I'm not a mod and cannot assist with your site registration.
ADTech is offline   Reply With Quote
Old 27-Jul-2018, 7:13 PM   #11
Tower Guy
Senior Member
 
Join Date: Dec 2009
Location: Delmar, NY
Posts: 1,236
Another trick is to place ferrite cores on the AC input and DC output of the power supply. Sometimes you can find these on used equipment such as VGA cables.
Tower Guy is offline   Reply With Quote
Reply

Bookmarks

Go Back   TV Fool > Over The Air Services > Special Topics


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off




All times are GMT. The time now is 3:23 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © TV Fool, LLC