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comcast today odd signal story !

Posted: Wed Sep 17, 2008 9:42 pm
by renovation
to day i see a Comcast van driving very very slow down my street . the Comcast drivers looking at a meter in the truck as he driving like 5 mph. has his hazards flashing as he doing this .he was going down then he turn around and comes back up at 5 mph -no bull . he pulls just past my house and gets out and pulls out this gadget. it looked like something out of a movie . he pulls what looked like 2 antennas out the side of this grass green hand held gun. and it making a high pitched squeal sound .then he starts walking up to the house across the street . he going all around under the 2nd story front deck ,one side and the other of the home. the squeal gets stronger and weaker. then he starts knocking on there door .im on my front deck watching all this. i informed the guy that there is know one home .we get talking and he tells me why he was there .
this blow me away totally. i guess the cable equipment was having a problem and leaking the signal and it was interfering with the aircraft that flys overhead.
he left a red tag on the door and also told me that if the owner didn't. call comcast in 24 hours and make a appointment to do the repairs . then comcast would have to come back out and disconnect his service from the pole. any of you ever heard of a cable signal jamming a aircrafts signal ?

Posted: Wed Sep 17, 2008 10:01 pm
by blade_146
When I worked at the cable company we did the same thing. I always thought it was a little far fetched to think that it would interfere with aircraft too but thats what I was told. Who knows. Guess the next time a plane crashes we an blame on it the cable guy lol

Posted: Thu Sep 18, 2008 8:34 am
by TheSovereign
lol whoa! i mean the amount of power to it would take to get thru an aircraft's sheilding would be huge. he could have been bs'ing and just detected an open AP on a customers line or something

Posted: Thu Sep 18, 2008 9:00 am
by normalicy
Actually, it doesn't take much to cause interference. The FCC is pretty strict about that stuff. My uncle build a radio once that cause so much interference that the entire neighborhood couldn't receive signals.

Posted: Thu Sep 18, 2008 9:12 am
by renovation
Q: What problems can signal leakage cause?

A: Cable signal leakage can interfere with any of the radio services that happen to be using the same frequencies as the cable operator within the vicinity of the cable system. Such interference, especially on the safety-of-life radio services, can disable the communications of safety personnel or airplane pilots. When such interference occurs, it can endanger the lives of the public and hamper the rescue efforts of safety personnel.

Q: Can signal leakage interfere with aircraft navigational and communications equipment?

A: Yes, there have been several documented cases of interference to aeronautical communications between airplanes and air traffic control.
http://www.fcc.gov/mb/facts/sig_leak.html

Posted: Thu Sep 18, 2008 12:19 pm
by Key Keeper
I used to mess around with 10/11 meter radios. If im not mistaken anything over 4 watts is illegal. I would get complaints all the time about bleeding over people tvs/radios/phones/ect. I never payed too much attention to it though till one day i was sitting at a red light and my talk back voice got very loud. I then realized that a local sherifs department officer was sitting at the light next to me and I was bleeding through the PA speaker mounted on his bumper. He didnt seem to happy about it but at least I didnt get a ticket. Oh was running a tiny bit of power.....1800 watt deadkey, 2600 watt swing......Radio>2 pill linear driver>6 pill linear amp....(two 20v alternators and 4 8v batteries wired in parrallel-series pair)...made a great garage door opener remote as well

Posted: Thu Sep 18, 2008 6:42 pm
by Badmojo
Was expecting a story about theft of service as thats usually what they do as improper cable splices can leak and tracked down in the same manor

Posted: Thu Sep 18, 2008 7:48 pm
by Pugsley
meh.. used to work at a place that had an ultrasonic welder for welding vinyl. well every time you would make a hit with it the cable company would lose all local channels. provided the cable head end was right across the street. We could have been dicks and kept on running it since it didn't break and FCC laws. It was not a transmitter or a reciever, so the FCC can't do jack about it.

Posted: Mon Oct 20, 2008 11:23 pm
by renovation
called comcast tonight again due to loss signal. this week they replaced all the splitters in house .i replaced the router 2 -3 weeks ago .today i swapped out my modem. and now tonight i loss signal again .the tech on the phone said he readding a bad signal level . guess iim going to have to have all the cables in my place replaced next .im talking all the lead / runs next. glad they get to do that and not me .

Posted: Mon Oct 20, 2008 11:43 pm
by normalicy
Not that you should need to, but I ended up adding a cable signal booster right where it enters my home & it seems like since then, I rarely lose signal. Used to be pretty regular before. I'd make them work for their money though. I know that they rip me off.

Posted: Tue Oct 21, 2008 12:06 am
by renovation
normalicy wrote:Not that you should need to, but I ended up adding a cable signal booster right where it enters my home & it seems like since then, I rarely lose signal. Used to be pretty regular before. I'd make them work for their money though. I know that they rip me off.
got a link ?

Posted: Tue Oct 21, 2008 6:27 am
by wvjohn
a little off topic but on interference. I was visiting the huge radio telescope facility in southern wv. They are located in an official federal fcc "quiet zone" where there are no transmitters of any kind permitted. It was located there because it sits in a valley and there are no cell towers within 90 miles, etc.

any kind of radio interference can be reflected off the hills and corrupt their signal, so they monitor 24/7 across the full spectrum that they use. During one project they started get regular spikes on a frequency that indicated some type of 120v electrical short. They have the vans and sent them out to triangulate the source. It was a cold winter, and it turned out a guy had put an electric blanket in his doghouse. The dog had chewed it a little bit, creating a short.

They bought him a nice heating pad for outdoor use. End of interference.

Posted: Tue Oct 21, 2008 7:02 am
by FlyingPenguin
Reno, I had the same problem. My house is on 20 acres and the cable from the street is 600+ feet so I get a pretty weak signal to start, and then I have 5 TV jacks and the cable modem. I was plaqued with weak signal problems for a long time.

Once they replace your splitters, clean your connectors, and run a home run cable to the box for the modem there's nothing more to do than install an amplifier.

DON'T buy your own amp. Anything you buy will probably not be commercial quality and may not work with a cable modem. Get the amp from Comcast - you won't find it any cheaper and they'll install it for you PROPERLy.

Talk to Comcast and request an amplifier from them. They generally resist installing an amp except as a last resort because amps are a tech support nightmare (an amp is potentially one more failure point to worry about). If you can't get the guy on the phone to agree to install the amp, talk to the tech when he comes out again to fiddle with the wires. Most techs are happy to install it if they know you understand the downside (that an amp can take a lightning strike for instance, and that you'll eat the cost of the amp).

I finally got them to install the amp here 3 years ago and never had a problem again with the modem or with weak signal for the cable boxes.

The Amp they installed for me has something like 8 outputs. They installed it in a larger than normal box outside that replaced the splitter box. The power supply is located in the house and backfeeds the power through the coax cable back to the amp.

You have to buy the amp from them, but they'll install it. They charged me $50. You own the amp and if lightning takes it out you have to pay for a new one. Worth it for me - even if it fried once a year it's worth it to have a reliable signal. Never have taken a hit yet though and this is the lightning capital of the U.S.

Posted: Tue Oct 21, 2008 9:06 am
by normalicy
That's not a bad price on the amplifier FP. I'd go that route if they offer it. Otherwise, here's what I got which is of good quality.

http://www.circuitcity.com/ssm/Motorola ... tDetail.do

I've seen it go for under $40 on sale at various places, but not this week.

Posted: Tue Oct 21, 2008 10:08 am
by FlyingPenguin
Mine is an Electroline EDA 2800. It's a commercial grade unit with an internal surge protector and it's fully weatherized. You could even mount it without a box if you had to, but it's better if it's not rained on just to keep the jacks from corroding.

A quick Google searched turned it up in several places, including Amazon.com's Marketplace, priced from $60 to $119.

If you can get Comcast to install it for $50 like they did for me, it'd be a steal.

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And this is the power supply inside the house:
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