Not gonna start another MonsterCable vs XXXX war here..... We are one of the largest Monster cable Cable CI dealers inthe country.(We've won monster CI dealer of the year 2 years running now) Thats what we use....... Is there "Better" cables out there... Perhaps.... Probobly even.... but thats not an argument I care to partake in.... WHich is why I have been absent from most of the other monster bashing threads around here.

As for the RG comment.. I certainly conceed that Quad Sheild RG-6 is NOT the correct wire to run.... But a Flexible standed RG-59 is the same thing "Component" video cables are. Whether its labled individually as RG-59, or sold bundled in three as "Component" makes no difference as far as what the cable is capable of transmitting.
[Link: bwccat.belden.com]

Persoanally, I'd rather run Cat-5 in most situations now..... That way Ican run Composite, S-Video, Component and even RGBHV to any room and call it a day.

Just dont beat me up in a dark alley if you ever get the chance to meet me Ted.... ;)

What the hell?


Yes, and a million dollars will guarantee you a seat on the bus. But you don't NEED a million dollars to get on the bus, and you don't NEED a 3 gHz sweep -- at least not above a couple hundred megs.

RG59 will work very nicely to a couple hundred megahertz, especially in lengths under a hundred feet. We used to use it for VHF antennas, for pete's sake!

The issues are:
First, the center conductor often is not solid copper in cable made for antenna use. It is copper-clad steel (CCS). Skin effect is real at antenna and cable frequencies, but video goes down to 60 Hz, so the center should be solid copper. Also, electricity flows faster in copper than in steel so the lower frequencies of the signal will arrive later (through the steel) than the small amount that flow on the surface (if any, due to skin effect).

Second, the shield, braid, foil, whatever are aluminum on RG6 (and also on some obsolete RG59 antenna cables, but the point is, aluminum is used on ANTENNA cables). Aluminum has higher resistance than copper, so you may have more attenutation; again, short runs will be less affected. More importantly (in the past), you could not solder to aluminum, so you had to use an F to RCA adaptor, which is likely to fail some time in five years or so. Why would you set yourself up to have to use a part that will fail?

Third, now that compression fittings, even RCAs, are available for RG6, you should have no problem adapting the old wire. But if you had a green tinge then, you will have a green tinge now, because that sounds like lack of blue, and you have a wire problem.


It does. Welcome to a newbie who is clear, has accurate information, and has a good attitude. That helps the rest of us have a good attitude, too.

By definition "swept" means the cable is tested at many frequencies. Swept to 3GHz means that the cable is tested from DC to 3GHZ, at a number of frequencies, and the performance of the cable is guaranteed over that frequency range.

Here's a site that shows fairly generic specs for RG6 and RG59.

[Link: antennasystems.com]

Simon,

I think you have a basic misunderstanding of skin effect. You comment that "Video signal however travels
through the center of the wire". Here you imply that the impedance will be greater because it's not traveling through the copper plated to the steel.

The truth is that at DC, that current will flow through the entire cross section of the wire, in inverse proportion to the impedance of the material. You will find that for any center conductor, that loss increases with increasing frequency. This is always true, because even if the center of the conductor had an impedance 100 times that of the outer layer, at DC and lower frequencies, the center material still lowers the impedance of the conductor, because the two conductors are in parallel.

Think of it this way... if you have a 1000 ohm resistor, what resistance do you need to put in parallel with it to increase the resistance to greater than 1000 ohms?
Answer: You can't. If you use an infinite resistance, you still have an impedance of 1000 ohms. Even if the resistor you add in parallel is 1000000 ohms, the total impedance of the system is 999 ohms, less than the 1000 ohms of the original resistance.

So... if the 1000 ohm resistor in the example above is the outer skin effect, and the inner conductor is the resistance we are adding, you'll note that the energy loss can only increase with frequency. Or, the lower in frequency, the better a cable of a given center conductor type will perform.

I'm quite familiar withthe proces of sweeping cables..... I still dont see what a 3Ghz RF signal has to dowith a 90Mhz Baseband HD signal..

So... in conclusion, monster is still overrated crap but we won't fight about it today cause it's Wednesday - and RCA compression fittings will do fine on RG-6 quad even though I might get a ticket from the HD Police for the technical infraction.

Is that right or did I miss something? Dang guys, what was the question?

I said I ran RG-59 Interconnect cable, ususally this...

[Link: sheersoundcable.com]

Then I sweep, usually with this...

[Link: homedepot.com]

or this...

[Link: homedepot.com]

I prefer the first one since it fits into my trunk easier. I don't have to slam it quite so hard.

Ok... I'll agree. The term swept to 3GHz means nothing other than the manufacturer tells you what the results are!

Obviously a cable swept to 3GHz that is at -70dB per 100M at 100MHz is not what you would want for this application.

I suspect Steve Garns problem had less to do with the cable specs, and more to do with the cable itself. Perhaps there was a poor connection, cable was kinked or stretched, resulting in reflections in the transmission line.

I believe the above for several reasons. First,, I don't think anyone will be able to see the difference between RG59 and RG6 in a 40' run. The math works out to, 40' is about 15Meters, RG59 is about -10dB at 100M, RG6 is about -5dB per 100M. That puts the attenuation at -10*(15/100) or -1.5dB for RG59, and -5*(15/100) or -0.75dB for RG6. A difference of only 0.75 dB, this is gonna be really hard to see, if even possible, as this is where the difference is at it's worst. As frequency decreases, the two will perform even closer.

The fact that he was seeing one color predominate, leads me to believe that one of the cables was damaged or not connecting well. I remember hooking a projector up at home, and playing the Matrix to test it out while I'm working in the room. The movie looks really good, as it plays a while, something seems off. I look at the connections on the back of the projector, and the red component cable has popped out. I push it back in, and I get the correct reddish skin tones. I was messed up by the fact that the opening scenes of the Matrix are in green, when the rest of the movie proceeded that way, my brain didn't immediately comprehend it.

If the cables didn't have the bandwidth necessary, the detail in the video would be lost. It would look more like an S-Video connection. He didn't complain about loss of detail, so the bandwidth of the cable was fine.

So, I think his issue was with one of the three cables. I think this cable was damaged at some point. Not necessarily during install! A drywall guy could have put a nail or screw through the cable, dropped a sheet on edge between studs and kinked the cable, etc, etc.

As far as issues about skin effect, and copper vs copper plated steel center conductor. Skin depth at 100MHz is not mutch of an issue. The real issue between the copper and copper plated steel, is that it's difficult to use solder on connectors with the copper plated steel. And if you get a bad solder joint, you will have problems.

As far as issues with copper vs aluminum braid, this will be reflected in the attenuation characteristics for the cable. Since it was one color that was giving him problems, I dont think the loss in the cable was the issue. The difference between the aluminum and copper is that with the aluminum, you can forget soldering! You won't get a good solder joint. If the cable has aluminum braid, you need to use a good compression, snap/seal, or crimp connection.

This has probably been the most accurate and useful post in this thread

I'll try and say it more clearly this time. Swept to 3GHz means nothing by itself, because this doesn't tell you what the loss is at any frequency. What matters is the loss at the frequency of interest.

A cable swept to 3GHz will by definition tell you how the cable performs at 50-90MHz, because the performance will be stated at a variety of frequencies, that is what swept means: The frequency was varied/swept from DC to 3GHz and the data recorded.

Reminds me of the creep on the early St. Elswhere shows who passed a polygraph by not lying. He said that he indeed did commite the crime, and since that was the truth, he passed the polygraph test. Seems nobody asked what the questions and answers were....

You could sweep a garden hose to 3 gig and label it swept to 3 gig. That means nothing unless the results of the sweep are specified.

As for skin effect,

From an article by Steve Lampen --

"As frequencies go higher and higher, electronic signals begin to move from the whole conductor to the outer layer, the "skin" of a conductor. When you are in the megahertz, this can be a serious effect.

This is why, for instance, CATV/broadband cable has copper-clad steel center conductor. At Channel 2 (54 MHz) and above, only the skin of the conductor is carrying the signal. The rest of the wire can be anything: aluminum, steel – it could be empty! Steel is most commonly used because it is cheap and it is strong."


That is why you don't want to use CCS unless you are keeping well below about 50 mHz. It's okay for 480i, but starting to be a problem for 480p and worse for higher frequencies.

Good lord. How will we ever get our customers to agree with us when we can't even agree with each other?

These "which coax" threads (which occur much too often) are the most hair-splitting bickering-inducing posts on this board.

Every aspect of our projects have a scientific side & a practical side. For someone to say "I'm right & you're stupid" because their choice of cable reads a smoother sweep on a scope is nothing short of childish. It's real-world applications that matter, and anyone who's ever connected an HD cable box to a 42" plasma knows you can send 1080i component using just about anything that's coaxial. I've used everything from Tara Labs component cables to the crap the cable guy leaves behind, and never has a customer been disappointed with the picture.

These threads with the "I know more than you" attitude behind them have got to stop.

Just my .02c - flame away.

- Doug @ BHS

Well, here's my .02:

I'm sure everyone agrees that the better the coax grade, the lower the loss per distance. RG-11 is better than RG-6, which is better than RG-59. However, the criteria for RF and for other signals (audio and video) is a bit different.

RF signals are less dependent on the conductor material than other signals are. Standrd RG-6 has a copper-clad-steel center surrounded by an aluminum-braid/aluminized-mylar shield, and would benefit little from all copper.

However, audio and video signals (whether analog or digital) do benefit from all-copper conductors. Plus, at typical interconnect lengths, the loss/distance ratio is practically irrelevent, even for whole-house A/V distribution.

In other words, non-RF signals do not benefit by using RG-6 over RG-59, and may be detrimental. Plus, RG-59 is thinner, more flexible, easier to find connectors to fit, and is easier to terminate, especially if soldering is desired.

Of course, the usual YMMV, IMHO, and other disclaimers apply.


edit: By the way, "coaxial" means sharing a single axis; therefore, any single-conductor-plus-shield cable is, by definition, coaxial. We typically thing RG-x when 'coax' is mentioned, and interconnect when 'shielded cable' is mentioned.

Remember, though, that any number of conductors can be shielded, either individually, collectively, or both. S-video cable is indeed two single-conductor-plus-shield cables in a single overall jacket (usually), or sometimes Siamesed. /edit

This message was edited by Larry Fine on 05/27/05 11:39 ET.

Ernie,

I was following you until the last paragraph. In the first two paragraphs you make the case that most of the signal is carried in the skin of the conductor. Ok... I'll buy that... I agree!

The last paragraph is where I believe your reasoning falls apart. You say you Do Not want to use Copper Covered steel unless you are below 50MHz? In other words you are saying that copper covered steel is not a good choice at frequencies above 50MHz. Am I understanding your point correctly to here?

Yet we know from your own paragraph above that at 50MHz nearly all the energy is carried in the skin at this frequency. Since a CCS conductor's skin is copper, how is this worse that solid copper? Since you yourself state that the skin effect is the issue at these frequencies, solid copper is Not Needed above 50MHz, because the signal is flowing in the skin. Therefore at 50MHZ copper covered steel is acceptable.

My point is that for a 40' long component video cable, that you can choose RG59 or RG6. The specs of the cable itself are almost a non issue. I think someone would have difficulty buying something that wouldn't work well. The biggest issue is terminating the cable well (With CCS or aluminum braid, you better be using crimp, snap/seal, or compression connectors, as you can't solder them well.) and making sure the cable is not damaged during install or construction.

I believe he meant "you don't want to use CCS unless you are keeping well above about 50 mHz."