Increasing Cable TV signal strength
 

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.

Increasing Cable TV signal strength
 

In message , amdx
writes
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.


Despite your long 170ft drop cable, were you getting good analogue
signals before the change to digital? If so, it could be that something
is not right. Normally, even if you have had only fairly mediocre
analogues, the digitals are good.

Otherwise....
It sounds like your signals are just too weak. As things are, and if you
can, the obvious fix would be to overcome the substantial loss of the
170ft drop cable by fitting an amplifier at or near the utility post
(not at your end), and power it with low voltage via the coax from your
end (ie similar to a line-powered masthead antenna amplifier). However,
you would need to consult with the cable company to see if they were OK
with letting you do this. It could be that they might be able advise you
on the most suitable amplifier to use. It's not rocket science, but you
have to be a little careful not to break any of their rules and
generally do anything they don't approve of.
--
Ian

Increasing Cable TV signal strength
 

On Feb 8, 2:00*pm, amdx wrote:
Hi All,
I'm on a boat, about 170ft from the utility post.

That's about 10dB loss at midband for RG6.

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 was just a 3dB boost.

* 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?

Really? There are such things a power inserters and compatible drop
amps that allow you to power the amplifier over the cable from the
user end. For RG6 18ga stranded that is about 0.6V loss at 250mA and
therefore doable,

I would run two cables if there was a way to make it increase signal
strength.

Forget it.

* Getting anymore from the cable company is not an option.
* *Any ideas to get a better signal?
* * * * * * * * Mikek


Use a 15dB gain drop amp with power inserter, but that's just a guess.
Would help if you actually knew signal levels like what the receiver
requires for optimum reception and what the cable co sources. Putting
the amplifier at source gives you a typical system noise figure of
3dB, but putting it at your end limits your NF to 10dB minimum from
the start.

Increasing Cable TV signal strength
 

In article ,
amdx wrote:
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?

Adding an amp at the cable box isn't all that likely to work... you
can try it, but don't get your hopes up. Unless the amp has a
significantly lower "noise figure" than the RF front end in the cable
box, all you'll be doing is adding noise... the desired signal will be
stronger, but the noise will be stronger yet.

Something you could do, is add a single-port RF amplifier right at the
utility post splitter, where your tap comes off of the feed. You can
buy amplifiers of this sort which are designed to receive "phantom
power" through the coax cable... you'd install a "power injector" at
your boat, which feeds a DC voltage up the coax to the amplifier.
This is probably your best bet:

- It would amplify the signal before it's attenuated by the 170-foot
cable run.

- It won't require a power supply at the post... just at your
boat, where you already have power.

- It shouldn't interfere with the other taps on the
splitter, even when the amplifier is not receiving power from your boat.

You'd be looking for an "antenna mast" type of preamplifier. The
Channel Master 0068DSB or 7777, Winegard AP-8700 or AP-8275 or
HDP-269, AntennaCraft 10G212, or one of the Blonder Tongue Galaxy III
models might do the job for you. You'll probably want a "75 ohm in,
75 ohm out" model, which would connect directly to the 75-ohm coax.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Increasing Cable TV signal strength
 

On Feb 8, 12:00*pm, 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.

see URL:
http://www.dbsinstall.com/broadcast/vhf_uhf_freq_list.asp
41 is 324 - 330MHz and 42 is 330-336 MHz
cables attenuate more at higher frequency.

By ALL means, if you're going to add an amplifier, add it at the
source location, not at the receiver location
Cheap, but good, ones are available from microcircuits. Can you buy a
line driver from your CATV company?

I suspect the 'better' cable is only marginally better. What is the
EXACT cable you're using? what is its attenuation per foot per MHz?
You can buy extremely low loss coax, but you may have to send in your
first born. Go to a local NRTL [EMC Test Lab] and see if they can
(are willing to) order a length for you.

Find the highest channel you wish to receive and the frequency
associated with that. Now you can balance the amplifier gain with the
cable loss to determine if it will work. Note you already know that
170 ft of ?? cable gets you up to channel 41, so from that number you
can estimate just how much drop your receiver can take before it stops
receiving.

Increasing Cable TV signal strength
 

On 2/8/2012 11:00 AM, 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.


Are you sure it's a signal strength problem?
The cable guy should have been able to measure the signal at your cable box.
Are the people using the other taps having problems?
If you're on a boat, you might be at the end of the cable run.
In that case, you might be able to get them to crank up the gain in their
distribution amp.
Power at the pole is not a problem. You can get amps that are powered
through the signal cable to your cable box. Getting them to let you
install it
is another matter.
You can get MUCH better wire, for a price.

Signal strength is not the only problem with digital TV.
Reflections in the system can confuse the decoder. Are there
any unterminated cables on the other taps?

I have OTA antenna digital TV. Plenty of signal, but reflections
cause significant drop outs on some channels. More signal won't fix
that. In fact, I have a variable attenuator to REDUCE signal strength.
I tweak the signal level for fewest dropouts.


Might be electrical noise coupled in thru the ground system.

Bottom line is that you pay the cable company for TV reception.
It's their responsibility to provide you with a watchable signal.
You shouldn't have to tell them what to do. They should just FIX it!!

Increasing Cable TV signal strength
 

On 2/8/2012 2:17 PM, Ian Jackson wrote:
In message , amdx
writes
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.


Despite your long 170ft drop cable, were you getting good analogue
signals before the change to digital? If so, it could be that something
is not right. Normally, even if you have had only fairly mediocre
analogues, the digitals are good.


But, analog can be snowy but very watchable, digital an be pixalated
and stuttering without no sound or often no picture at all.

Otherwise....
It sounds like your signals are just too weak. As things are, and if you
can, the obvious fix would be to overcome the substantial loss of the
170ft drop cable by fitting an amplifier at or near the utility post
(not at your end), and power it with low voltage via the coax from your
end (ie similar to a line-powered masthead antenna amplifier). However,
you would need to consult with the cable company to see if they were OK
with letting you do this. It could be that they might be able advise you
on the most suitable amplifier to use. It's not rocket science, but you
have to be a little careful not to break any of their rules and
generally do anything they don't approve of.

I had not thought about a coax powered amp, Thanks.
Mikek

Increasing Cable TV signal strength
 

On 2/8/2012 2:36 PM, Fred Bloggs wrote:
On Feb 8, 2:00 pm, wrote:
Hi All,
I'm on a boat, about 170ft from the utility post.

That's about 10dB loss at midband for RG6.

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 was just a 3dB boost.

But that 3bd did get me a more consistent picture.

That got my signal to work almost all the time. I'd like to get the
signal to work 100% of the time.

Increasing Cable TV signal strength
 

In message , amdx
writes
On 2/8/2012 2:17 PM, Ian Jackson wrote:
In message , amdx
writes
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.


Despite your long 170ft drop cable, were you getting good analogue
signals before the change to digital? If so, it could be that something
is not right. Normally, even if you have had only fairly mediocre
analogues, the digitals are good.


But, analog can be snowy but very watchable, digital an be pixalated
and stuttering without no sound or often no picture at all.

You are quite correct. However, digital is generally capable of working
to lower signal levels than analogue. It's amazing how rubbishy digital
signals can be, yet still give perfect pictures - but don't expect
miracles!

Otherwise....
It sounds like your signals are just too weak. As things are, and if you
can, the obvious fix would be to overcome the substantial loss of the
170ft drop cable by fitting an amplifier at or near the utility post
(not at your end), and power it with low voltage via the coax from your
end (ie similar to a line-powered masthead antenna amplifier). However,
you would need to consult with the cable company to see if they were OK
with letting you do this. It could be that they might be able advise you
on the most suitable amplifier to use. It's not rocket science, but you
have to be a little careful not to break any of their rules and
generally do anything they don't approve of.

I had not thought about a coax powered amp, Thanks.
Mikek

I see that several others have also suggested a coax-powered amplifier.
[If the cable company can't give you more signal level, it's the only
solution.] As suggested, they should be able to provide a suitable
amplifier and power unit - or at least advise you what to use.
--
Ian

Increasing Cable TV signal strength
 

On 2/8/2012 2:47 PM, Dave Platt wrote:
In ,
wrote:
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?

Adding an amp at the cable box isn't all that likely to work... you
can try it, but don't get your hopes up. Unless the amp has a
significantly lower "noise figure" than the RF front end in the cable
box, all you'll be doing is adding noise... the desired signal will be
stronger, but the noise will be stronger yet.

Something you could do, is add a single-port RF amplifier right at the
utility post splitter, where your tap comes off of the feed. You can
buy amplifiers of this sort which are designed to receive "phantom
power" through the coax cable... you'd install a "power injector" at
your boat, which feeds a DC voltage up the coax to the amplifier.
This is probably your best bet:

- It would amplify the signal before it's attenuated by the 170-foot
cable run.

- It won't require a power supply at the post... just at your
boat, where you already have power.

- It shouldn't interfere with the other taps on the
splitter, even when the amplifier is not receiving power from your boat.

You'd be looking for an "antenna mast" type of preamplifier. The
Channel Master 0068DSB or 7777, Winegard AP-8700 or AP-8275 or
HDP-269, AntennaCraft 10G212, or one of the Blonder Tongue Galaxy III
models might do the job for you. You'll probably want a "75 ohm in,
75 ohm out" model, which would connect directly to the 75-ohm coax.

Hey thanks for the part numbers, I'll look into these.
Mikek