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3.1 Ingress

Ingress is basically the leaking IN of a signal. Ingress is bad, because it can totally trash a signal.

If there are any cuts, strips, bad crimps, or bad shielding on the line, TV channel 5 leaks into our CATV channel 5, and completely distorts the picture and the sound is usually messed up too. This happens a LOT with houses wired with RG59, because of the lack of good shielding. Also, if the conductor is exposed to the air at ANY point, that is an entry point for stray signal.

I apologize for the bad pictures, but these were taken with a digital camera. Whenever I get around to getting my TV Tuner hooked back up, I'll provide some much better shots. But for now:

Channel with ingress:


Same channel without ingress a few secs later:


Ingress, as it pertains to cable modem access

Two-way digital data signals are more susceptible than one-way signals to stresses in the condition of the HFC network. Degradation in video signal quality might not be noticed, but when two-way digital signals share the network with video signals, digital signals might be hampered. More information can be found here. (Thanks to JTRockville for providing this information)

Feedback received on this FAQ entry:
  • that is correct. ingress(noise) can cause modem to have reset or timeout. usually a t3 timeout. a t3 timeout is when a modem sends 16 cmts response requests and dont return a message back. usually caused by ingress(noise)... peace... home-computers.org

    2012-01-30 23:16:11

  • Ingress can cause issues for all of the customers on an entire node. I recently had a service call and one of the the neighbors on my tap was feeding ingress into the tap and may have been a contributing factor in my ongoing issue with modem resets. According to one technician I spoke with, one customer causing bad ingress can possibly disrupt an entire node.

    2010-11-16 14:18:16 (IowaCowboy See Profile)

  • Your link on page (3315), Cable modems and wiring issues, is broken. It's the one that links to Cisco (JtRockville). Just thought I would let you know. Later Man!

    2009-11-10 12:51:57



by Raydr See Profile edited by ergibbs See Profile
last modified: 2004-11-15 18:14:25

If you are experiencing ingress on your line, the FIRST thing to check are your connections. Make sure that all of your lines, from the wallplate to your equipment are ALL tight and secure.

Whenever I'm on a service call for ingress, the first thing I do is shake the wires behind the TV and see if it comes and goes. Half of the time that is the problem.

Push on connecters are NOT your friend and are a very common cause of ingress. Screw on ones are very annoying, but they are much more secure.

If that is not your problem, then it's probably the wiring. If you have a long cable running around the room from the cable outlet, take a look at it and make sure it says RG6 on it. If not, I strongly suggest you pick it up, throw it away, and head out to Wal-Mart and buy a decent quality cable.

If you've done this, and you still are experiencing ingress, then it's time to get some wires replaced. If you aren't scared of running new lines, go to your nearest hardware store (I recommend GrayBar) and buy a thousand feet of RG6 and start running new lines.

If you don't like doing work like this, see if your cable company offers any kind of wiring maintenance plan. They are usually pretty cheap ($2 or $3/mth) and will get you new lines run for free.

I recently went to a house to rewire it because they were having tons of problems. I located their junction and found this horrible piece of work:



Welcome to ingress hell.

Note by wth See Profile: You also need to pull the wallplate off and check the cable & connector on the backside of the plate also.

Feedback received on this FAQ entry:
  • I thought I would share this new product with you. BarrIER™ is a new connector and port technology that helps minimize RF signal leakage or ingress & egress to within the drop. I would be interested in hearing your feedback regarding our new product that will be available in 2014 - http://www.hollandelectronics.com/barrier.html

    2013-12-06 13:51:30

  • Many people fail to look inside the wall but I have found many problems here. I have found splitters inside the wall that were also hooked up backwards. Don't forget to check the coupler inside the plate itself. There are two tiny teeth inside the coupler that sometimes wear out and lose connectivity.

    2011-08-18 15:52:57



by Raydr See Profile
last modified: 2005-05-17 10:01:25

This is really a system by system question. In areas where there is potential for a lot of noise (metro areas, high population), they may be necessary. From what I've seen, generally no. I suggest that instead of leaving open jacks, that you just disconnect the line and use a smaller splitter. Not only will this prevent ingress from unused jacks, but it will also send more signal to the used jacks.

I also received this response from jkintner See Profile:

"I was just reading your cable modem wiring FAQ and bumped into this question. I'm a contractor in Las Vegas, NV. We actually require the termination of any open port or wall jack in the home because of leakage and ingress problems. Having an open port acts just like an antenna and ends up backfeeding signal back into the system.

One noted case was a customer having problems with their modem dropping off during the day time. We re-wired his house from tap to all outlets to try and fix the problem. After about 4 weeks of troubleshooting and getting an engineer involved, we found that a neighbor had an open port in a bedroom and was using a remote controlled car. The motor in the car was putting off just enough interference on the upstream carrier for the modem, that it was knocking our customer offline."

Feedback received on this FAQ entry:
  • there are none other than terminators, if you don't have none make appt for a tech to come in put them in, just point cause he should have them, we always do

    2012-01-19 14:59:05 (drcable See Profile)

  • How did you isolate it? Sniffer, Sentinal, etc?

    2011-10-08 20:22:12

  • I am a service tech for bright house networks in west volusia county, florida. We actually had a barrell at the base of a tread mill which was loose and took down an entire NODE due to the back feeding of noise onto the plant!

    2010-05-06 18:17:35



by jmo9 See Profile edited by ergibbs See Profile
last modified: 2003-04-17 09:03:23