Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: moojuice on June 11, 2013, 07:56:46 PM

Title: Source of REIN found (ECI modem hackers take note)
Post by: moojuice on June 11, 2013, 07:56:46 PM

I decided to switch on my HiFi radio to MW earlier this evening and was greeted with severe REIN noise which altered when I was typing or moving the mouse on my PC. The noise seemed very pronounced at around ~680 KHz (analogue dial). The noise disapeared when I unplugged this little gadget:

http://hackingecibfocusv2fubirevb.wordpress.com/2012/08/13/a-solder-free-uart-connection/ (http://hackingecibfocusv2fubirevb.wordpress.com/2012/08/13/a-solder-free-uart-connection/)

The TTL USB UART device which many of us have used to unlock ECI VDSL modems kicks out a lot of RF noise. Mine was purchased from Amazon, but it's identical to the one above. I was using mine as a serial adaptor for my Raspberry Pi, so I could use Putty as a terminal to it. Whilst I haven't ruled out my PC or Pi from being equally as noisy, just unplugging the TTL USB serial adaptor has reduced noise ten fold.

Can anyone else confirm this? Suffice to say it'll be used sparingly now. SSH all the way  ;D

Title: Re: Source of REIN found (ECI modem hackers take note)
Post by: asbokid on June 13, 2013, 02:49:26 PM

Hehe! Good discovery, though I'm not surprised!  Selling for little more than a quid, not much design effort will have been spent on suppressing RF noise.  :-X  On a related note, there was some question over USB3.0 and whether it interferes with 802.11 Wi-Fi.  Has anyone here noticed that?

cheers, a

Title: Re: Source of REIN found (ECI modem hackers take note)
Post by: JGO on June 13, 2013, 04:30:26 PM

TTL used to be notorious for RFI and I heard of one manufacturer's devices which produced a bust of 300 MHz (?) on each transition. If we are talking about WiFi on 2400 MHz this is the 8th harmonic of 300 ??? This could be what asbokid has heard of.

Title: Re: Source of REIN found (ECI modem hackers take note)
Post by: asbokid on June 14, 2013, 02:03:27 AM

http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/usb3-frequency-interference-paper.pdf

cheers, a

Title: Re: Source of REIN found (ECI modem hackers take note)
Post by: Chrysalis on June 14, 2013, 11:09:25 AM

everytime I see one of these threads I really hope its something I can find and get rid of noise.

never is :(