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Joerg[_2_] Joerg[_2_] is offline
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Default Increasing Cable TV signal strength

Michael A. Terrell wrote:
Joerg wrote:
Michael A. Terrell wrote:
Joerg wrote:
Michael A. Terrell wrote:
Joerg wrote:
Michael A. Terrell wrote:
Joerg wrote:
amdx wrote:
Hi All,
I'm on a boat, about 170ft from the utility post.
Recently our cable company switched to the wonderful world of
Digital TV. I got the new digital converter and had no picture.
I took the box back and got a second box, still no picture. So now I
suspect a weak signal and confirm that it is the cable length. The cable
company came out and gave me a better cable than I had installed. At
this point I have a picture but it is intermittent. The signal at the
utility post has 3 outputs and had a four way splitter, I suggested the
cable guy put in two 2 way splitters and give me the stronger (first) tap.
That got my signal to work almost all the time. I'd like to get the
signal to work 100% of the time.
Looks like the cable guys screwed up.
In your opinion.
If their company cable box doesn't deliver a useful and reliable signal
I call that screwed up. One pays for a service and expects to either get
it delivered as promised or money back.

... If they are delivering the level called for in
their franchise, they didn't screw up. It has always been up to the
customer to pay for or provide extra equipment for non standard
installs.

Mike's install does not sound non-standard. 170ft cable drop towards
premises which is fairly normal, plus the cable company's set-top box.
Grow up. That is an excessive length drop. A standard drop is under
100 feet. You think you know everything, and that the world has to live
by your rules. You don't, and it doesn't. ...
http://www.starvision.tv/lineup_res.htm

Quote "Maximum Drop Length 300 Feet"

Now that's what I call good service.

... I'll bet you've never even
seen a CATV franchise, or the dozen of pages of specifications agreed to
by both the CATV company and the local government. The CATV company
isn't a Santa Clause machine, and local governments know why there are
limits to the service provided. If there were't, no one could afford to
build or operate a CATV system. You've never designed a headend, or a
physical plant If they build to supply higher port levels, it has to
start at the headend, and requires closer spaced trunk amplifers. The
system noise goes up from all of the cascaded amplifers, and the
equipment runs hotter, withj a very reduced service life. When you can
design an RF distribution system of more than 500 MHz bandwidth and has
over 10,000 output ports, with the gain stabilized to a couple dBmv 20
miles from the headend and over a range from sub zero F to + 100 F then
you can tell me I'm wrong.

One headend I designed and built was only off by .1 dBmv at the test
port on the first trunk amp which was a half mile from the head end. If
you can do better than that, I'll listen to you and your opinions

See above. Obviously others can. And yes, I have designed RF broadband
power amps. Lots of them. Not just lashing up boxes but the actual
transistor level circuitry including layout guidance for the nasty stuff.

Fact is, if a cable company isn't competent to do a 170ft drop they
should decline the job. Otherwise it is a screw-up, plain and simple. In
our area they'd lose their shirts to the satellite guys because there
are many houses like ours where there is no reasonable way to get from
the street to the house with a 100ft limit. We have around 200ft that's
still there from the early 90's and the previous owner said cable TV
worked just fine for them. We are not subscribed because TV ain't that
important to us.

Yawn. You constantly harp about having to meet specs in medical, but
whine like a drunken jackass when other businesses have to meet their
specs. yes, they could design the sytems to 300 feet or more, but the
cost to every customer on the system would go up.

In medical I tend to push the envelope and so do the standards
committees. Sometimes based on what we do. I designed all my cardiac
stuff defibrillator-proof, always, although it was not the law yet. Then
they made it law, because it makes sense.



You do it because they wouldn't hire you if you couldn't meet specs,
just like every other consultant, engineer or tech. They might even
jail you for your incompetence for not meeting the specs.


Correct. And the spec for a competent cable company is typically 300ft,
as I have shown in the link. Plus the one below.


Believe it or not but I like to have to meet specs in medical because
they protect people. Including you.



Believe it or not, most technical people have that same standard.
You're nothing special.


Never said I was. Except that I do exceed standards at times where I
believe it is necessary. In the case of med electronics that has likely
saved lives. I do not subscribe to the idea that a standard is always
good enough. Because sometimes they are not.


... Would you like to pay
an extra 20% to 30% just so a very few locations can get better
service?

Out here we do not pay extra. Our cable companies out tend do use modern
technology, not cheap stuff from the 70's. A cable company that isn't
competent enough to do more than a measly 100ft would lose their
franchise rather quickly.



Once again the all knowing Jeorge shows his ignorance.


No. I suppose you know what MoCA is. Do you consider them ignorant?
Because they say the very same thing that I said. What matters is
today's state-of-the-art. Nobody cares about what it was in the 80's.
Today this is state-of-the-art:

http://www.cablefax.com/ct/sections/...ier_44237.html

Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..."

then

Quote "The maximum cable distance supported between the root and the
last outlet is 300 feet, with a maximum attenuation of 25 dB". And this
is for MoCA, not just cable TV.


1: You don't know what you're talking about, about the cost of
service. Any extra operating costs become part of the basic service
that everyone pays. You won't work for nothing, and the utilities don't
give them free electricity. The service companies don't repair the
equipment for free. Do you have any idea how many amplifiers, taps and
set top boxes are needed for 10,000 active ports? To provide hotter
ports require more amplifiers, and raises the system noise floor. You
'designed an amplifier'. Big deal. A lot of engineers 'designed and
amplifier' and those companies are long out of business. ...



So how many linear RF amplifiers above 1W have you personally designed
and guided through layout?

Hint: All my clients are still in business and I am sure will be for a
long time to come.


... Current CATV
amplifiers use hybrids designed specifically for the application and
they use them for many reasons. That just leave the design of the 60V
modified sine wave to DC power supplies, equalizers, gain control,
equalization and remote switching. Some locations also have remote
monitoring so the headend can check system status on a continuous
basis. It can also report outages when some of the equipment doesn't
respond. They can even detect power failures and monitor the battery
status in the standby power supplies to give them time to get a portable
generator to the area if it is an extended outage. The local
Brighthouse system remained in operation here for over four weeks after
a hurricane even though the only way to watch TV or access broadband was
with battery power or a generator.


If that company can't do more than 100ft they'd fail miserably in our
market. It's not just our house, it's also the neighbor to the west, and
the one after that, and ...


2: '70s CATV tech was 12 channel with no return path. It was crude,
discrete point to point designs that looked like a ham put together from
junk TVs while drinking cheap beer. They were touchy as hell, their
tempco sucked, and they were impossible to service without a fully
equipped test bed. the power supplies were simple, poorly regulated
linear supplies with 85 C electrolytics that died quickly in the
southern sun. The large diecast aluminum housing ran hot to the touch
without the sun hitting them. That stuff was pretty well all scrapped
out by the mid to late '80s by 36 or more channels with return
capability. There was so much construction of upgraded systems that
there was a severe shortage of new hardware through most of the mid
'80s.

That '80s tech was gone in all but the smallest systems by 2000.
Today most systems are 450 MHz or higher, and are 'Fiber Enhanced' to
provide telephone, broadband, movies on demand and pay per view services
by breaking the system into cells that cover a few hundred homes, or
less.

3: You know nothing about CATV franchises. 'A measly 100 feet' is
more than adequate for a hell of a lot of drops & house wiring. ...



No, it is not. If you don't believe me check out Cameron Park, CA,
especially the area of the Estates. Then tell me how you want to do that
with 100ft drops.


... If that
is what the franchise calls for, THAT IS THE SPECIFICATION, ...



And the franchise would get kicked out of the market around here. You
can't serve this market with a sub-par spec. The big automotive
companies had once exhibited a "Well, this is the spec and that's that"
attitude like you do in this thread. Then they learned, the hard way. In
part by essentially going on welfare which was embarrassing.


... no matter
how much you whine like Sloman. A city or county won't pull a franchise
over one or two people complaining about weak signals. ...



They will if there's a whole big crowd showing up at the next meeting.
Now I won't because I only watch the evening news via antenna. But I
know a whole lot of folks who would be miffed to be declined service
because they are literally addicted to the sports channels. Many would
just get satellite though, they market that quite aggressively these days.


... They receive a
fixed percentage of the system revenue every month, and the percentage
was set when the economy was up. If they pull the franchise, another
provider will offer a much lower percentage. It also involves legal
fees, and causes the rates to go up for the users.



The county folks have one much more important thing on their mind: How
to get re-elected. That's what'll matter most to them. They know that
seeing complaints about what many people perceive as a utility service
they have "rights to" in the paper is not the way to get re-elected.


... Why put up with all
that for a fraction of a percent of problems. Like people who built a
private road a mile long and want to pay the standard install fee when
it will cost about $15,000 to run a feeder for that one house. Or like
that marina. It isn't a street. It's private property. If they want
better service, let them pay for upgrades with .500 cable to each boat,
with a .500 to 'F" connector for each boat. That would only cost a few
hundred dollars a boat for materials. More if the cable is jacketed.
If it isn't it won't last long in salt air. Double that for the
hardware and labor to get a good idea of the costs.


Then answer a question I asked you before but you did not comment on it:
Why did Mike's cable provider not decline service? Obviously it worked
reliably in the analog days and now with DTV it doesn't. If they can't
handle the 170ft drop after the digital switch, why did they not inform
Mike, cancel the service on their part and send someone out to pick up
the set-top box?

[...]

--
Regards, Joerg

http://www.analogconsultants.com/