Jump to content


Welcome to DBSTalk


Sign In 

Create Account
Welcome to DBSTalk. Our community covers all aspects of video delivery solutions including: Direct Broadcast Satellite (DBS), Cable Television, and Internet Protocol Television (IPTV). We also have forums to discuss popular television programs, home theater equipment, and internet streaming service providers. Members of our community include experts who can help you solve technical problems, industry professionals, company representatives, and novices who are here to learn.

Like most online communities you must register to view or post in our community. Sign-up is a free and simple process that requires minimal information. Be a part of our community by signing in or creating an account. The Digital Bit Stream starts here!
  • Reply to existing topics or start a discussion of your own
  • Subscribe to topics and forums and get email updates
  • Send private personal messages (PM) to other forum members
  • Customize your profile page and make new friends
 
Guest Message by DevFuse

Photo

Wifi interfere with OTA


  • Please log in to reply
11 replies to this topic

#1 OFFLINE   PCampbell

PCampbell

    Icon

  • Registered
  • 1,434 posts
Joined: Nov 18, 2006

Posted 10 June 2013 - 06:41 PM

I find it hard to believe but a guy at work has RV at a park that added wifi for the park with multiple TX points. He got 10 or more channels with the antenna mounted on top of the RV. When the wifi went online he lost all but two?? It is a 2.5ghz system, the highest tv frequency is about 700mhz. Anybody see this and if so what did you do.


Edited by PCampbell, 11 June 2013 - 10:08 AM.

DirecTV since 1996

Slimline 5 SWM 16
HR24-100
HR24-500
HR24-500

HR44-500
ATT uverse internet


...Ads Help To Support This SIte...

#2 OFFLINE   photostudent

photostudent

    Godfather

  • Registered
  • 295 posts
Joined: Nov 08, 2007

Posted 11 June 2013 - 05:26 AM

No RF transmitters are perfect and can generate some harmonics. Band pass filters were a common cure for SD TVs and should work for HD as well.

#3 OFFLINE   P Smith

P Smith

    Mr. FixAnything

  • Registered
  • 20,051 posts
  • LocationMediterranean Sea
Joined: Jul 25, 2002

Posted 11 June 2013 - 09:06 AM

then the WiFi equipment is in violation of FCC rules and must be shutdown, any RF engineer with spectrum analyzer and own antenna would find a source of the RF interference

while I don't see how it happen, I wouldn't blame the WiFi access points


  • RasputinAXP likes this

#4 OFFLINE   kenglish

kenglish

    Icon

  • Registered
  • 972 posts
  • LocationSalt Lake City, Utah, USA
Joined: Oct 02, 2004

Posted 15 June 2013 - 09:24 AM

If the Wi-Fi is really at 2.5 GHz, it should not be a problem, unless the TV signals are very weak and the antenna is very close to the Wi-Fi.

Other frequencies could be used, and if those are closer to the TV frequencies, they may be overloading the sets' front-end, or overloading any preamps being used for TV.

 

The other idea is, the router for the Wi-Fi system may be causing interference, or the customers who are now using their Wi-Fi may have routers that are interfering.



#5 OFFLINE   PCampbell

PCampbell

    Icon

  • Topic Starter
  • Registered
  • 1,434 posts
Joined: Nov 18, 2006

Posted 16 June 2013 - 12:51 PM

The stations are weak and the antenna is less than 50ft from the wifi antenna.


DirecTV since 1996

Slimline 5 SWM 16
HR24-100
HR24-500
HR24-500

HR44-500
ATT uverse internet


#6 OFFLINE   P Smith

P Smith

    Mr. FixAnything

  • Registered
  • 20,051 posts
  • LocationMediterranean Sea
Joined: Jul 25, 2002

Posted 16 June 2013 - 02:57 PM

All the postings will not fix the problem.

 

You should pass it to hands of professional RF guy

 

or

 

buy cheap USB DVB card what support SDR, install SDR_Sharp [free] software and drivers, scan the spectrum and walking around find the damn source of interference !



#7 OFFLINE   kenglish

kenglish

    Icon

  • Registered
  • 972 posts
  • LocationSalt Lake City, Utah, USA
Joined: Oct 02, 2004

Posted 17 June 2013 - 08:03 AM

Is there a preamplifier on the TV receiving antenna? I suspect there is, if it's designed to go on an RV.

The close-by Wi-Fi signal is possibly overloading the (very wideband) input of the antenna amplifier.

Replacing, or seriously modifying, the antenna is all that would help.

 

If no amplifier...........

At the UHF frequencies that are used for TV, it might be advisable to put several of those Radio Shack ferrites on the cable near the TV antenna, and several on all of the cables that feed the Wi-Fi antenna. Of course, some of the interference from the Wi-Fi may be radiated directly from the Wi-Fi equipment, not all thru the antenna. That would take a few more ferrites on the power and data cables.



#8 OFFLINE   P Smith

P Smith

    Mr. FixAnything

  • Registered
  • 20,051 posts
  • LocationMediterranean Sea
Joined: Jul 25, 2002

Posted 17 June 2013 - 09:39 AM

kenglish, we are dissing WiFi 2.4 or 5 GHz band equipment's possible polluting on RF 40-900 MHz band; while it is possible to create EMI for that, we must count the max power of WiFi devices (I recall 500 mW per FCC rules), probably 200 mW or normally 100 mW.

Perhaps we have a deal with _faulty_ device(s), in this case it must be discovered and fixed ASAP.

 

 

 

I would call FCC and complain - they have special road service what would come and measure and will help find the problem.



#9 OFFLINE   PCampbell

PCampbell

    Icon

  • Topic Starter
  • Registered
  • 1,434 posts
Joined: Nov 18, 2006

Posted 17 June 2013 - 12:19 PM

Problem solved, the park changed the channel of the Wifi.


DirecTV since 1996

Slimline 5 SWM 16
HR24-100
HR24-500
HR24-500

HR44-500
ATT uverse internet


#10 OFFLINE   P Smith

P Smith

    Mr. FixAnything

  • Registered
  • 20,051 posts
  • LocationMediterranean Sea
Joined: Jul 25, 2002

Posted 17 June 2013 - 08:01 PM

the WiFi device(s) is still not kosher if it emit parasitic signal in low RF band  (VHF/UHF)  while it must stay with 2.4 GHz


Edited by P Smith, 17 June 2013 - 08:02 PM.


#11 OFFLINE   PCampbell

PCampbell

    Icon

  • Topic Starter
  • Registered
  • 1,434 posts
Joined: Nov 18, 2006

Posted 18 June 2013 - 05:47 AM

I thought all models needed to be tested before release to the public but quality control may not be all that good.

DirecTV since 1996

Slimline 5 SWM 16
HR24-100
HR24-500
HR24-500

HR44-500
ATT uverse internet


#12 OFFLINE   kenglish

kenglish

    Icon

  • Registered
  • 972 posts
  • LocationSalt Lake City, Utah, USA
Joined: Oct 02, 2004

Posted 18 June 2013 - 11:22 AM

I'm going to send a link to this thread, to Charlie Rhodes, who is the leading expert on DTV interference.






Protected By... spam firewall...And...