Background radio noise issues/TiVO/Alarm ?.

Posts: 2

Hello there, searched through a lot of posts and unable to determine a definitive solution or replicate problem.

I have switched over to Vonage in Feb/Mar and the cutover occurred last month from the RBOC, and I have been troubleshooting these issues for ~month.

Vonage tech support has been non-existant as I think I have multiple issues, and they can not clearly identify where the issues are. Rolling Eyes

Here is the deal.
I have the Linksys RT31P2 router, this is in place between the Motorola Surfboard Cable Modem (uncertain of model #) and the Microsoft MN-700 Base Station WAP.

Connected to port 1 of the Linksys, is my Uniden 2.4GHz base station phone, with 2 expansion phones (only need an outlet, no phone line) throughout the house. When plugged directly into port 1, bypassing the home wiring altogether, I have not noticed anything discernable pertaining to noise.

Enter the issue:
Outside at the Telephone CSI (Customer Service Interface) for the phone box, I unplugged line1 and line 2 incoming from the RBOC, thereby leaving the house unplugged from the outside.
I plug the house phone jack with the Uniden plugged into a 2 way extender into jack 1 of the Linksys and I get an AM radio station in the background, with varying amplitude as it relates to barometer, cloud cover, humidity, and other atmospheric conditions.
I also have a Vtech 2.4Ghz expandable phone set plugged in at the kitchen and 1 handset upstairs. Totalling 5 phones, 2 expandable bases througout the house. The phones function properly, and I have not had issues, other than noise, which can be so loud it over rides the conversation. I have not noticed whether or not this is noticeable from the outside (other end of the phone call) or not.

In trying to troubleshoot this, I had the thought that I changed my ground plane in going from POTS, to Voip. I checked the RG-6 coming in at the Cable CSI, and verified the HSD was properly grounded and followed all paths of ground to confirm there were no ground loops, and the electrical HSP (House Service Panel) was also properly grounded and it all followed typical NEC, Bellcore, and Telcordia grounding standards.

I know twisted pair copper works well as an antenna, although my house is four years old, and wired with CAT5 for the in-home wiring. There is a 66 block type punch down in the basement where a central line from outside comes in and all phone jacks are home run to that location, and distributed out to the block.

I have taken VOM measurements and not found anything to be out of place. My suspicion is that because of this noise, it is also creating the connection errors I am experiencing on both the TiVO and the alarm monitoring modems.

My thought is to plug the jumper into jack2 with a 600Ohm, 1W resistor across pins 2/3 of a RJ-11 to attempt that solution.
If the noise goes away, then I can try the #019,*99 ,*70 ,#01341 codes and give it a rip.
The TiVO is the Directv unit, Samsung SIR-S4040R.

I appreciate any and all help you can provide, I apologize if this specific issue has been covered, but in a couple hours of searching I could not located anything.
At this point I am not certain if this is a wiring issue, grounding issue, equipment issue, or something else entirely.

Posts: 1424 · Posted: Wed Jun 15, 2005 1:05 pm Post subject:

I saw posts about noise being introduced via the unterminated phone port 2, but I never heard of it being AM interference. However a quick way to determine if the jumper will help you is to plug a phone into the second port and take it off hook.

Resolving Telephone Interference contains some basic information that may be useful to anyone experiencing radio on their telephones.

RID - Radio Interference Damper also has a checklist of things to do to attempt to eliminate radio noise.

IIRC, the telephone ground is almost always located in the phone company side of the NID (CSI). This is typically not a problem because the phone company wires are normally the source of interference. However unplugging the NID probably removes the ground for the house phone wiring.

Your TiVo codes:
",#019" and ",#034" are valid codes (the comma is, as I understand it, required. Try it without anything first, then try 34 and finally 19.

I am unsure of what "#01341" will do, if anything.

Posts: 2 · Posted: Wed Jun 15, 2005 1:31 pm Post subject:

Thanks for the reply, the ,#01341 was a mis-type someone posted on a thread about utilizing ",#0341" with the extra 1 in there...

I was thinking more about this, and the ONLY place I didnt check for ground was the 66-block panel downstairs. THAT could be the problem.

I will get the shorting block and check the grounding and go from there.

Thanks!

Posts: 49 · Full Forum Member Joined: Jan 28, 2005 Posts: 49

One of the things that can cause this to happen is a defective/cheap telephone device (Phone,Answering Machine,Caller ID Box). Please try unplugging all of your telephone devices from the various jacks around the house. Plug each one in to the line and check for the am station one at a time. When you plug the device in and the AM station is there when you pick up the line, that is the defective device.

Normally this is caused by something in the telephone device acting as a diode and rectifying the RF from the broadcast station.

Here is a nice primer for telephone RFI, though it has a ham radio bent.