New house being built 1

[wires]

Very interesting comments from threedots (s in morse code?). However I still do not see any technical support for the following:

>3. Since you will (should) have the cable company
>do this for you, don't be afraid to run quad-shield.
>You won't be sorry.

First - since we are discussing this in a cabling forum I would assume most of the readers here would be able to purchace and properly use coax termination equipment (Thomas and Betts SNS line is my fave).

Second - there is NO TECHNICAL REASON to use quad shield in residential wiring. As threedots said "The higher the shielding, the less likely that EM will be a problem." which is true. However I cannot imagine a situation where the slight inprovement in shielding would be of any help in a residential enviroment.

Belden (they should know...) recomends their type 1694A as a RG6 type cable for "Home Theater and High-End Audio". This is not a quad shield cable, it is 100% foil with 95% braid.

To see the recomendations go to:

http://bwcecom.belden.com/college/college.htm

then click on "Cable Training" then "Technical Papers" then "Recommendations for Home Theater and High-End Audio".

 

[daronwilson]

Hmm, three dots...could be EEE too if you sent it slow enough. Kudos to wires, i too use the Snap N Seal line of connectors, they seem to be very good and solid. So happens my cable company does as well which makes them happy when I do installs for them. Yes, we do quite a few. The cable company wont crawl under buildings or go in attics. If you want it stapled across the outside of your house or on the baseboard, you are in luck. Anything else, I get the majority of the work.

As for shielding, can you have too much of a good thing? I suppose you can have more than you need. We used to use double shielded stuff all the time in RF work at mountaintop sites where interference was the norm. At 200 watts or so for two-way work keeping it all inside the coax in the building was important. With TV coax, we are more interested in keeping the signal out.

I agree it would be tough to present a case where dual shield coax failed and the quad shield didn't. One thing I did find out in my earlier years, my ham radio caused interference with the neighbors TV cable, and of course, it was MY fault. I went over, replaced every screw on "F" fitting with a crimp on one and made their signal useable. However, it still showed up when i transmitted. The cable company came out, dug in a new line from the pedestal and pulled the old line out of the dirt. Low and behond, there were several nicks in the jacket of the wire exposing the foil, and some through the foil. New wire with no nicks and no interference. I suppose it is less likely that you will get damage through all four shields of the quad shield than just two shields. Though, you could put it in metal conduit and have it all shielded and protected.

I guess we use QS because the customer many time asks for it. Personally, if they want a better product or are convinced that it is better and it is technically sound, I dont have a problem selling it to them. In actual practice, I'm not sure I could prove it to be necessary for any routine installation.

two dashes, three dots, three dots, two dashes

It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[threedots]

"The cable company came out, dug in a new line from the pedestal and pulled the old line out of the dirt. Low and behond, there were several nicks in the jacket of the wire exposing the foil, and some through the foil. New wire with no nicks and no interference. "

Jeesh! I hope they used conduit this time!

No dashes, no dots, no code... just "to be continued"..., and continually striving to learn.

Somewhere back about the middle of this thread discussion (I believe it was beginning with "wires" Feb 24th posting), mention was made regarding running Cat5 and Coax in the same conduit. Thus the basis of my remarks. Please do not extrapolate to mean this applies to all installations and circumstances.

Cat5 for full rate transmission simply does not like EMI. If we are talking about Cat5 alone in a conduit, that's one thing. If we add coaxial cable for various other applications (and their corresponding frequencies and voltages), then we are talking about potentially compounding problems. It was to this mixing within a single conduit that I responded.

I didn't mean to mislead the forum. Sorry it was taken that way

As for the users' experience with cable companies, I suppose that varies widely from cable company to cable company. Mine, for instance, never buried wire without conduit, and would routinely go under crawl spaces and into attics.

ThreeDots (no dashes, no code, no EEE)...

 

[mnmcomm]

on the conduit thing posted earlier.

The NEC says 360 degrees between pull boxes, but the TIA/EIA says there should be no more than 180 degrees, and no more than 100' between pull boxes. Pull boxes should not be used to changed directions of the conduit run either.

one day they all will be in harmony, hopefully. Matthew Masi RCDD