Question on splitting cable signals....

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My cable TV reception is "OK" but I am thinking of ways to reduce signal loss and improve the picture if possible.
- I have about 6 TV's in my house.... 3 on the main living floor, and 3 in the upper bedrooms. - My cable comes in the basement, and is split 4 ways, with one going to the upstairs. - The upstairs lead is split again 3 ways for the bedrooms.
In theory, would it be better to split the incoming siganl 6 ways in the basement, and run 3 independant cables to each bedroom?
What about in practice? Would 1 less slpit in the chain improve things?
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Bill wrote:

Most splitters have db loss printed right on them. Hook the shortest run to the hightest loss on the splitter. You might think about getting an amp to jack up the dB's first. Just don't put the amp where there is little or no signal or you will just be amplifying noise. Get a good amp, cheap ones just make it worse. Its always best to have home runs to each TV but thats not always feasible. Also make sure if your splitting a signal your not splitting it on the high db loss side of the splitter.
Good Luck, Rich
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Speaking of amps ..... A couple of years ago we had 5 TV's and an amp, gemini I think. We were eating dinner when we heard a loud beep, beep, beep coming from outside. There was a Comcast cable truck outside. The worker rang our bell. He said he detected an illegal condition that needed to be resolved. If we refused, service would be stopped. We let him in. He said that our amp was in violation and had to be removed. We complied and he went away. The reason he gave was that it interfered with aircraft, believe it or not. We never hooked it back up. It was very scary to have somebody pull up outside and "scan" our premisis. Makes you wonder what else they have.
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that's BS. they don't want you getting different TVs in your house without paying extra.
A coax cable is a shielded transmission line, it's got the neutral wrapped around the inner conductor and it shouldn't radiate anything, certainly not enough to reach airplanes. while a really bad amplifier could leak out RF, at 100MHz the wavelength is about 3 meters and an antenna must be at least 1.5 meters. I don't think the amp could work as a good antenna for the cable frequencies. maybe someone in front of your house could detect some leaks but not an airplane 10Km above.
it's more likely that the amp was cheap and it did create interference on their own network, or that they simply wanted you to pay extra.
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No, more likely the amp was feeding back signal through the line and a neighbor complained. In checking that out, he may well have found you amp was also going illegal. The cable companies hare sensitive to what you hook up to THEIR lines as it can cause problems for other customers.
I might add that if you are violating the contract you have with the cable company by feeding more TVs than you are paying for or are using pirate equipment to get stations you are not paying for it is YOU who are cheap and stealing from the cable company and all the users who are not stealing.
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On Thu, 01 Jan 2004 21:24:24 GMT, "Joseph Meehan"

They also could have found the amp, especially if it's a cheapie, during a drive-by leakage test.
CATV companies are required to meet certain leakage standards. Some have a very hard time keeping their outside plant in passing condition, maybe they don't want you blowing the bogie for them. <G>
Barry
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wrote in wrote:

BINGO,you have the correct answer.
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The amp could be a cheapo one,and acting as a noise generator.Or overdriving an input,or had a loose connection.
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snipped-for-privacy@aol.com (Sasal Suzi) wrote:

It is basically a radio, your amplifier was emitting signals, IE broadcasting, and he was able to pick it up, with a more sensitive receiver than TV or radios.
The frequencies used by air craft, and police are right above the FM band (what would be 109-120 on the dial or so), which is between channels 6 and 7 in the TV spectrum.
So yes, a bad TV antenna product can cause problems with public safety.
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yes, but there's no antenna in an amplifier. let's say the amp is 10 cm long, if there's a 10cm trace on the PCB it could radiate at 1.5Ghz, not 100MHz. I can see how someone outide your house can pick up stray emissions, but I don't see how these emissions would reach an aircraft 10Km above.
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Uh, the line cord on that amp was probably a bit longer than 10 cm, huh?
If the manufacturer didn't give a shite about keeping the rf leakage down, then the amp could have been lighting up the house's whole electrical distribution system with rf. Odds are that's what the cable company picked up.
Now do you "see why". (Ducking...)
You've undoubtendly noticed labels on all sorts of electronic equipment stating that they comply with certain FCC rules with regards to rf leakage. Those "thick lumps" you often see on cables coming out of computer monitors are ferrite chokes, used to block rf currents from going any further.
Just my .02
Happy New Year,
Jeff
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then
distribution
I just didnt' think a system could be so badly designed that the signal path interferes with the power supply. in that case yes, there's an antenna in there, bu the fix is simple: get an amp that is not complete shit.
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No, there are long (relative) cables plugged into it.
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ya but those are shielded they pass signals in the hundreds of megaherz anyway, with or without an amp. if they weren't shielded they'd radiate either way.
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A loose F connector (or an improperly installed one)can allow leakage,or a corroded connector;the corrosion acts like a diode,creating harmonics from the many signals on the cable.One of the cable channels may have the same,or be close to a frequency used by aircraft.
Tha amp itself could have problems,perhaps overdriving an internal stage enough to cause EMI radiation.
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cheap TV amps (including Gemini as the OP stated) were notorious for RFI at one time. I think they have been forced to provide a cleaner product now.
Enuf
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Sasal Suzi wrote:

Your amp was leaking RF, and the tech was picking it up with a RF leak detector. All cable companies are required by the FCC to conduct these test and fix any leakage. The leaks can interfear with the public safety, Police and Fire comm. and Airline communications. If the FCC was to have found the leak the Cable Company in question could have been fined. That was the only reason he came to the house and asked you to remove it. He could careless how many outlets you had installed in the house. Techs don't usually give to craps about outlets and charges not being collected because they're highly underpaid and overworked.
I should know I have been in the cable business for 25 years and just recently said good riddance to it. I owned a cable construction business and probably placed 100 of thousands of miles of cable up until some idiot cable inspector (Charter) working in cable for a year told me I was doing it wrong. That was the last straw. I retired from it and am happily doing home improvement work. Anyone want to buy a couple of T-40c's
Rich
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Reminds me of England not so many years ago when folks had to pay an annual license fee/tax for each TV in a home, even though the signals they received were coming through the ether. The government had trucks which cruised around neighborhoods sniffing for the IF frequencies leaking out of TV sets and whacked you if you had an unregistered set.
I dunno much more about that, but I'm guessing the tax supported the BBC or something like that. Maybe that's still a common practice is some parts of the world?
Jeff
Jeff Wisnia (W1BSV + Brass Rat '57 EE)
"If you can smile when things are going wrong, you've thought of someone to blame it on."
Sasal Suzi wrote:

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snipped-for-privacy@aol.com (Sasal Suzi) wrote in message

When I worked for the FAA, I received pretty intensive training on tracking down sources of RF interference. You would be amazed at what odd stuff generates interference - even nonpowered things like a loose metal crossarm brace on a wooden telephone pole. The most common things though are items attached to TV's, especially amps. When we found the home or business where the interference was coming from, we were not allowed to take any action to correct the problem. Rather we had to contact a third party -like the cable company, power company, phone company, etc. Then they had to take action or face losing their licenses. This sounds like what happened in your case. As stated by other posters, the aircraft VHF frequencies are in the 115Mhz to 145Mhz range, just above the TV frequencies. But don't forget about harmonic frequencies - the offending item could be at a much lower frequency and the harmonic be in the aircraft band. And the offending item does not have to put out enough power to reach an aircraft. It only has to reach the ground antenna of the Air Traffic Controller.
Enuf
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snipped-for-privacy@aol.com (Sasal Suzi) wrote in

He was checking for EMI,electromagnetic interference,and it's required by Federal law.That's one of the main problems for cable companies,and they do get fined by the FCC for it.They weren't 'scanning",they drive around with a sensitive receiver with a directional antenna,that points in the direction EMI is coming from. Loose or corroded F-connectors can cause it,too.
One other thing,all amplifiers ADD noise to the signal in addition to boosting the level.The cable companies usually deliver to the home the lowest signal level practical to further reduce their EMI radiation.
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