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Question about coax cabling

rrizzojr
01-15-2008, 03:33 PM
First of all I'd like to say hello to everyone who reads my post and inform all that I am new to this forum.

I just had cablevision installed for those that know of Optimum. I also bought a Samsung 46" HDTV LCD 1080p.

When the cable/internet/phone was installed, the technician said that the wiring in the wall that is fed from the box outside is the old RG-59 cable and today's standards are RG-6.

I am terribly disappointed with all channels that are not HD channels and even some of those that are HD. The quality of picture is poor.

Would the RG-59 be the most likely cause of this?

The HDMI monster cable over the standard component cables really had no noticeable change in quality. I really don't know if HDMI monster cables make much of a difference to begin with over standard RCA cabling however, if degradation from outside supply to inside patch over exists, I am most positive that the cables used inside won't show noticeble difference.

Thanks,
Russ

Scottnot
01-15-2008, 07:46 PM
I just had cablevision installed for those that know of Optimum. I also bought a Samsung 46" HDTV LCD 1080p.

I am terribly disappointed with all channels that are not HD channels and even some of those that are HD. The quality of picture is poor.
Too bad. You should not have allowed the installer to leave until you were satisfied with the picture quality.
Your suggestion that "some" HD channels are ok, while others are disappointing is a bit odd however.

When the cable/internet/phone was installed, the technician said that the wiring in the wall that is fed from the box outside is the old RG-59 cable and today's standards are RG-6.

Would the RG-59 be the most likely cause of this?
VERY unlikely, unless the cable runs are over 100' or 200', or the cable is somehow damaged; even then, it does not seem to be the source of your problem.

The HDMI monster cable over the standard component cables really had no noticeable change in quality. I really don't know if HDMI monster cables make much of a difference to begin with over standard RCA cabling however, if degradation from outside supply to inside patch over exists, I am most positive that the cables used inside won't show noticeble difference.
Uh . . . I think I agree - there should be no significant difference between picture quality when using component cables over HDMI cables.

In any event, I would get the installer back.

Mark M
01-16-2008, 10:07 AM
Depending on the quality of the cable the RG-59 may not be able to carry the entire bandwidth signal. For the most part it should carry a cable signal, satellite service may be a different story. Most signal issues are caused by poor connectors being installed. Make sure the white dielectric is flush with the metal inside of the connector and the center conductor is completely clean, no braiding touching it and no filmy residue from the dielectric left on. The center conductor should also be less than 1/8" above the top of the connector. Use a compression fitting. Do not use a crimp on fitting that will distort the circumfrence of the cable.

Scottnot
01-16-2008, 10:30 AM
Depending on the quality of the cable the RG-59 may not be able to carry the entire bandwidth signal.
That's not correct; RG59 is totally capable of carrying the full bandwidth.

For the most part it should carry a cable signal, satellite service may be a different story.
The only exception I know of is Dish Pro, which requires 2.3Ghz rated cables. Since the OP has cablevision, there should be no problem.

Most signal issues are caused by poor connectors being installed. Make sure the white dielectric is flush with the metal inside of the connector and the center conductor is completely clean, no braiding touching it and no filmy residue from the dielectric left on. The center conductor should also be less than 1/8" above the top of the connector. Use a compression fitting. Do not use a crimp on fitting that will distort the circumfrence of the cable.
Agreed.
Yet, the problem does not sound like a cable or connector issue.
More like STB or settings.

rrizzojr
01-16-2008, 12:12 PM
Agreed.
Yet, the problem does not sound like a cable or connector issue.
More like STB or settings.

What does STB stand for? Not familiar with all the abbreviated terms!

Scottnot
01-16-2008, 02:05 PM
Sorry. STB = Set Top Box

rrizzojr
01-16-2008, 10:25 PM
Okay I called Optimum and they said that the signal strength from the Central Ofice to my Explorer 8300 HD-DVR is good. No signs of stressed signal. They told me to bring my Explorer 8300 back to central office and they will swao it with another one. I suppose this is what you are referring to as STB!

Scottnot
01-17-2008, 06:00 AM
Yes, correct.

Mark M
01-18-2008, 11:43 AM
"That's not correct; RG59 is totally capable of carrying the full bandwidth."

I prefaced my comment with " Depending on the quality of the cable" I have seen RG-59 copper braided cable that is unable to carry a signal over 900 mHz. It is intended for aerial antenna use and or CCTV use, but some people see RG-59 and think it can be used for today's cable and or satellite systems.

Scottnot
01-18-2008, 12:29 PM
"That's not correct; RG59 is totally capable of carrying the full bandwidth."

I prefaced my comment with " Depending on the quality of the cable"
Still, RG59 is totally capable of carrying the full bandwidth.

I have seen RG-59 copper braided cable that is unable to carry a signal over 900 mHz. It is intended for aerial antenna use and or CCTV use, but some people see RG-59 and think it can be used for today's cable and or satellite systems.
And indeed, in almost all cases . . . it can.
I have never seen a RG59 cable that has not been specified to at least 1.0 gHz.
With the exception of Dish Pro noted previously, none of today's cable and/or satellite systems use bandwidth above 900 mHz anyway.
In fact many older systems do not use more than 450 mHz.

It's just that suggesting that RG59 is not up to the task or will not carry the signal is sort of a "the sky is falling" warning to the less well informed. Just about any quality of RG59 will suffice except in very rare situations.

SavoR
01-19-2008, 04:10 AM
Still, RG59 is totally capable of carrying the full bandwidth.


And indeed, in almost all cases . . . it can.
I have never seen a RG59 cable that has not been specified to at least 1.0 gHz.
With the exception of Dish Pro noted previously, none of today's cable and/or satellite systems use bandwidth above 900 mHz anyway.
In fact many older systems do not use more than 450 mHz.

It's just that suggesting that RG59 is not up to the task or will not carry the signal is sort of a "the sky is falling" warning to the less well informed. Just about any quality of RG59 will suffice except in very rare situations.

RG59 May have specs to 1.0ghz, but is it entirely recommended for carrying digital/hd signal? Hardly.

I am a comcast technician, and when I see RG59, I replace it immediately because that cable causes issues easily. I have seen a 10' piece of RG59 be the cause of 10+ missing channels on someones STB. I would strongly recommend the cable going to that tv be RG6. Now if you aren't impressed with the HD signal coming in, depends on what you have, if you have Dish, I wouldn't pay money for their HD, half of it is fake.. Comcast, every channel has true HD, atleast 720p. If you have cable going straight to the TV without a STB, you should only be recieving locals in HD if your tv has an HD tuner in it, which I would assume so. Otherwise, if you got a STB, with a true HD channel you are looking at, and you are not impressed with the 'quality' you see on your screen, then it is the TV thats having the issue. If the signal is too low on cable line, your picture quality wont degrade, it will either pixelate, or just disappear all-together.

Scottnot
01-19-2008, 08:42 AM
RG59 May have specs to 1.0ghz, but is it entirely recommended for carrying digital/hd signal? Hardly.
Well, based on "specifications" - it most certainly is!
If you can cite any authoritative source that offers any reason why a RG59 cable should not be "recommended for carrying digital/hd signals", I would certainly like to see it.

I am a comcast technician, and when I see RG59, I replace it immediately because that cable causes issues easily.
Again, source citation would be helpful.

I have seen a 10' piece of RG59 be the cause of 10+ missing channels on someones STB.
Hardly likely, since the loss of only certain channels would indicate a bandpass problem whereas a poor cable would cause degradation on all channels or selectively on channels at higher frequencies.
To the extent that it is possible, particularly with a short length of cable, it would most likely be caused by either a severely kinked or crushed cable, or poorly installed connectors on the cable . . . certainly not by the difference between RG59 and RG6.


. .. if you got a STB, with a true HD channel you are looking at, and you are not impressed with the 'quality' you see on your screen, then it is the TV thats having the issue.
Unfortunately, this is what the cable company would like all consumers to believe. In reality, it is totally incorrect.
There are often weak analog signals, defective STBs, and other defective hardware that can cause picture quality problems.

If the signal is too low on cable line, your picture quality wont degrade, it will either pixelate, or just disappear all-together.
On an "all digital" system, this is usually the case.
However in analog systems, this is hardly the case; in fact, it is totally incorrect.

The incongruity of your statements greatly diminishes the usefulness of your information.

SavoR
01-25-2008, 06:23 PM
Well, based on "specifications" - it most certainly is!
If you can cite any authoritative source that offers any reason why a RG59 cable should not be "recommended for carrying digital/hd signals", I would certainly like to see it.

Ever heard of the term 'Skin Effect'? The fact that the gauge on RG59 cable is much smaller than RG6, the frequencies on the higher end degrade much quicker because of this. Also, the characteristic impedance difference coming from RG6, to RG59 is different. A mismatch of that sort can cause a loss of channels, or even issues with your signal.

Again, source citation would be helpful.

What, that I am a technician? I've been dealing directly with Cable issues every day for over a year. I believe I would certainly know more about what causes issues on a cable line more than you would.

Hardly likely, since the loss of only certain channels would indicate a bandpass problem whereas a poor cable would cause degradation on all channels or selectively on channels at higher frequencies.
To the extent that it is possible, particularly with a short length of cable, it would most likely be caused by either a severely kinked or crushed cable, or poorly installed connectors on the cable . . . certainly not by the difference between RG59 and RG6.

Let me put it this way.. ALL STORE BOUGHT COAX CABLES ARE CRAP! Reason being is the connectors themselves. I've walked into hundreds of trouble calls, and 9/10 times being its store bought equipment/cabling.

Unfortunately, this is what the cable company would like all consumers to believe. In reality, it is totally incorrect.
There are often weak analog signals, defective STBs, and other defective hardware that can cause picture quality problems.

Funny, I was referring to a digital signal. But the topic in case was the Weak signal itself, if you wanted me to dive in to other things that could cause picture issues on your box, I've got plenty more.

On an "all digital" system, this is usually the case.
However in analog systems, this is hardly the case; in fact, it is totally incorrect.

The incongruity of your statements greatly diminishes the usefulness of your information.

Yeah, I would like to see some source of your experience with cabling aside from your boasting on knowledge on this forum. Please learn how a cable system works before you try to talk about RG59 being okay to carry digital signal.

Scottnot
01-25-2008, 08:44 PM
Ever heard of the term 'Skin Effect'? The fact that the gauge on RG59 cable is much smaller than RG6, the frequencies on the higher end degrade much quicker because of this.
Yes, "Skin Effect", as you rightly suggest is part of the equation regarding cable attenuation, and indeed RG59 uses a smaller inner diameter conductor (20 awg; 0.8mm) than RG6 (18 awg; 1.0mm); although the difference is hardly considerable, but is in fact rather slight.
Consider that equivalent quality Belden cable results in the following attenuation for RG59 vs RG6 for 100' at 1.0 gHz.
RG59 - 7.6 dB
RG6 - 6.0 db
Let's see, that's 1.6 db at 1.0 gHz over 100' of cable . . . hell, that ain't snot.

Also, the characteristic impedance difference coming from RG6, to RG59 is different. A mismatch of that sort can cause a loss of channels, or even issues with your signal.
Wow, had to look that one up; let's see . . . characteristic impedance:
RG59 - 75 Ohms
RG6 - 75 Ohms
Hey, what about that! So where's the mismatch gonna come from?

What, that I am a technician? I've been dealing directly with Cable issues every day for over a year. I believe I would certainly know more about what causes issues on a cable line more than you would.
Now, I certainly can't comment on how good or bad a technician you may be, but if you must know, I did spend about 25 years in the CATV, RF and Microwave industry . . . none of it as a tech however.

Let me put it this way.. ALL STORE BOUGHT COAX CABLES ARE CRAP! Reason being is the connectors themselves.
Wrong again.

I've walked into hundreds of trouble calls, and 9/10 times being its store bought equipment/cabling.
mmm, and my industry experience tells me otherwise.

Funny, I was referring to a digital signal. But the topic in case was the Weak signal itself, if you wanted me to dive in to other things that could cause picture issues on your box, I've got plenty more.
I hope you won't embarrass yourself any further.

Yeah, I would like to see some source of your experience with cabling aside from your boasting on knowledge on this forum. Please learn how a cable system works before you try to talk about RG59 being okay to carry digital signal.
No boasting, simply commonly available facts.
For attenuation values, check any cable manufactures spec sheets.
For characteristic impedance values, check any manufacturers spec sheets.
Anything specifice upon which you would like to see an authoritative citation, just ask; it's no problem.

Likewise, can you cite any authoritative source to support your incorrect information.