Michael Coslo wrote:

I don't know exactly how it's done now, but when I worked in the Cable
industry many moons ago, we had a lot of adjustment we could make. Even
more, we had variable by frequency attenuators so we could ensure that a
flat signal showed up.


Those are 'Equalizers' and used to cancel the cable losses. There is
some adjustment in the trunk amplifiers, but some brands just used a
plug in equalizer marked with the rolloff in dB while others had both.
The coarse plugin, and a variable equalizer to level the trunkline for
'Proof of Performance' tests.


--
You can't have a sense of humor, if you have no sense.

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.

a. They should be putting enough signal on that cable to overcome the loss.

b. They should be able to measure the amplitude of pilot signals at your
end of the cable and tell you how much above minimums they are.


I don't has access to electricity at the utility post, so an amp is
out. Although I could try an amp at the cable box end. Is that reasonable?
I would run two cables if there was a way to make it increase signal
strength.
Getting anymore from the cable company is not an option.
Any ideas to get a better signal?
Mikek


PS.

When the signal fails it seems channel 41 is ok and above 42 it breaks up.
Curious to know if there is an unusual frequency jump between those two
digital channels.



If all else fails you may need an amp. What Fred means with drop amp is
usually called a "mast preamplifier", like this:

http://www.amazon.com/Uhf-Vhf-Antenn...748729&sr=8-20

I don't know this particular one but essentially it should be
weather-proof. It gets its DC voltage via the coax, from a wall wart
that would plug in at your boat. So no need to run a power supply cable
up there.

Don't go for too much gain. This dreaded DTV falls apart rather easily
on the slightest distortion or cross-modulation. Not sure if the above
amp can handle that. You might need a more expensive one. Michael
Terrell might know which ones are good. What matters is dynamic range.

Also, make sure you have a perfect 75ohms match at your end. The cable
box from the cable company should provide that. if you have Internet
and/or phone through them as well check that connection so it doesn't
cause reflections. On a boat at sea stuff can corrode quickly.

Oh, and don't dare to watch that boobs channel while your wife's on the
boat :-)

--
Regards, Joerg

http://www.analogconsultants.com/

On 2/8/2012 7:01 PM, 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.

a. They should be putting enough signal on that cable to overcome the loss.

b. They should be able to measure the amplitude of pilot signals at your
end of the cable and tell you how much above minimums they are.


I don't has access to electricity at the utility post, so an amp is
out. Although I could try an amp at the cable box end. Is that reasonable?
I would run two cables if there was a way to make it increase signal
strength.
Getting anymore from the cable company is not an option.
Any ideas to get a better signal?
Mikek


PS.

When the signal fails it seems channel 41 is ok and above 42 it breaks up.
Curious to know if there is an unusual frequency jump between those two
digital channels.



If all else fails you may need an amp. What Fred means with drop amp is
usually called a "mast preamplifier", like this:

http://www.amazon.com/Uhf-Vhf-Antenn...748729&sr=8-20

I don't know this particular one but essentially it should be
weather-proof. It gets its DC voltage via the coax, from a wall wart
that would plug in at your boat. So no need to run a power supply cable
up there.

Don't go for too much gain. This dreaded DTV falls apart rather easily
on the slightest distortion or cross-modulation. Not sure if the above
amp can handle that. You might need a more expensive one. Michael
Terrell might know which ones are good. What matters is dynamic range.

Also, make sure you have a perfect 75ohms match at your end. The cable
box from the cable company should provide that. if you have Internet
and/or phone through them as well check that connection so it doesn't
cause reflections. On a boat at sea stuff can corrode quickly.

Oh, and don't dare to watch that boobs channel while your wife's on the
boat :-)

Been trying to think of something funny to say about that...
Best I got is, she would say, "mine look better than those!

amdx wrote:

On 2/8/2012 7:01 PM, 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.

a. They should be putting enough signal on that cable to overcome the loss.

b. They should be able to measure the amplitude of pilot signals at your
end of the cable and tell you how much above minimums they are.


I don't has access to electricity at the utility post, so an amp is
out. Although I could try an amp at the cable box end. Is that reasonable?
I would run two cables if there was a way to make it increase signal
strength.
Getting anymore from the cable company is not an option.
Any ideas to get a better signal?
Mikek


PS.

When the signal fails it seems channel 41 is ok and above 42 it breaks up.
Curious to know if there is an unusual frequency jump between those two
digital channels.



If all else fails you may need an amp. What Fred means with drop amp is
usually called a "mast preamplifier", like this:

http://www.amazon.com/Uhf-Vhf-Antenn...748729&sr=8-20

I don't know this particular one but essentially it should be
weather-proof. It gets its DC voltage via the coax, from a wall wart
that would plug in at your boat. So no need to run a power supply cable
up there.

Don't go for too much gain. This dreaded DTV falls apart rather easily
on the slightest distortion or cross-modulation. Not sure if the above
amp can handle that. You might need a more expensive one. Michael
Terrell might know which ones are good. What matters is dynamic range.

Also, make sure you have a perfect 75ohms match at your end. The cable
box from the cable company should provide that. if you have Internet
and/or phone through them as well check that connection so it doesn't
cause reflections. On a boat at sea stuff can corrode quickly.

Oh, and don't dare to watch that boobs channel while your wife's on the
boat :-)

Been trying to think of something funny to say about that...
Best I got is, she would say, "mine look better than those!

And you know what you'd better reply!

Cheers

Phil Hobbs

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 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.


--
You can't have a sense of humor, if you have no sense.

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.

--
Regards, Joerg

http://www.analogconsultants.com/

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. 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


--
You can't have a sense of humor, if you have no sense.

On 2/9/2012 9:35 PM, Michael A. Terrell wrote:


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. 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



Cool! You seem to know what you are up to.

Can you put rough numbers around what you mentioned? Like what are
providers legally required to deliver at the far end of the drop?

Thanks.

tom
K0TAR

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.

--
Regards, Joerg

http://www.analogconsultants.com/

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.
I don't has access to electricity at the utility post, so an amp is
out. Although I could try an amp at the cable box end. Is that reasonable?
I would run two cables if there was a way to make it increase signal
strength.
Getting anymore from the cable company is not an option.
Any ideas to get a better signal?
Mikek


PS.

When the signal fails it seems channel 41 is ok and above 42 it breaks up.
Curious to know if there is an unusual frequency jump between those two
digital channels.

Well, you could add an amplifier at the splitter where (nominally)
there is no power.
Use the coax center conductor for power; inline capacitors allow
signal to pass and feeding center via small choke allows DC but no signal.
Once upon a time there were little adapters that did this AC/DC thing...