Installing RG6/U Cable using Wall Plate Connectors, any diff ?

[dandhack]

I will be running new RG6 cable, is there any differance in the wall plate connectors? some places advertize 1Ghz others do not specify. Is there any signal loss using the connector? should I even consider it? or should I just run the cable out of a wall plate with a hole in it and run the cable directly to the TV / Cable Modem / Cable Box?

I'm new to this, so any help would be great.
Thanks

[akirby]

There can be some signal loss with a connector but this is the same as an inline coax connector. As long as you use a good quality device and connectors and it's the only one in the line I don't see a problem.

[eliwhitney]

Hi dandhack -

I couldn't be certain from your 'post' but - as long as you are busy at this, why not 'spend' just a tad more & use quad coax ? And, do buy your own compression termination tool, NOT a "crimper" for the coax ends!

As akirby already said, do not "skimp" on that specific wall plate termination.

Since all this will be "behind" the bulk of the HDTV anyway, I prefer to Not spend the monies at all & do exactly what you asked - use only a "telephone line / small hole" plate , rather than Any other - avoids a 'double connection'....simply go on - uninterrupted - to the "RF" input in question

>>>>>edited to add ....P.S.....<<<<<<<<

Don't forget to put coax thru that plate hole Before compressing the terminal ???

[dandhack]

Thanks,
I did get the RG6 Quad Cable with compression connectors and tools.
I think I will just run the cable through the wall and cover it with the wall plate with the small hole.
Because I will be doing this a few times, I know that I will forget to put the cable through the hole first, at least once.

Thanks again for your help.

[wellvideo]

Just an FYI, DirecTv does specify that the feed throughs (F-81's) and even the ground block along with the coax should be frequency sweapt to 3 Ghz. Such items are available. They are typically identified with a BLUE center insert. Check out [url] http://www.fadfusion.com/sitesearch.php ... erydept=00 and http://www.fadfusion.com/selection.php? ... 0161200695
This may be "hype", however I have seen regular F-81's degrade over time. probably depends on the enviroment. My system is installed with all components that meet DirecTv's specs of 3 Ghz.

I hope this helps.

Regards.....Lyle

[regman]

Not only have I had F-81's fail over time but I personally consider them a "single use device" and don't reuse them if I have to disconnect them for any reason. I have also had faulty grounding blocks - in one case attentuating 50% of my signal strength. Analyzing (under a binocular zoom microscope) those things, it almost appears they were originally designed for RG58 which had a smaller center conductor. RG6 stretches them out and the connection is compromised. The less connections the better. Leave lots of service loop because you will periodically want to cut off an inch or two and replug the cables. Be sure to use waterproof types (with rubber o-rings) for outdoor use and a little silicon grease on the threads won't hurt either. Shrink Tubing over the whole deal is not a bad idea either. Always have drip loops in your outdoor cables and NEVER into any splices, splitters or connectors. I ran all of my cables directly from the multiswitch to the STB's with one exception - the grounding block (you only have to ground one lead). It is essential for safety and your OTA antenna must have a grounding block as well. Since I have all copper pipes (which are attached to a earthen grounding rod per our local code) I was able to use a simple saddle clamp for grounding the blocks. Use at least 12G (green insulated) wire for grounding.

I have looked for RG6 hardware and other than the larger ID "F" connectors haven't found any specifically designated for RG6. If anyone know where to procure some please post it.

It amazes me that you can have a 20 grand home theater system with a $.39 connector being the weak link.

3GHz huh? That requires some pretty specialized test equipment to measure. Most lab grade oscilloscopes rarely go above 1GHz and those that do are considered very high end (my 1GHz scope originally cost over 30G). Frequency counter are rare at that frequency as well. I have an "MIT" quality electronics bench with all fluke, HP (Agilent) and Tektronix gear and other than a few frequency generators on my RF bench (Spectrum ~ 512KHz to 13GHz) I can't measure anything higher than 1 GHz and that's with a sampling plug in in a Tektronix 7104 series mainframe scope. Oh, and then there's the test probes - they cost a fortune as well. I would seriously doubt that those litttle pocket testors are of sufficient quality to make 3GHz measurements (like the one Direct TV and other installers carry around ).

[Roger Halstead]

You forgot to say what you are getting the signal from be it cable, satellite, or off the air. Unless you have a very weak signal you can put a half dozen connectors in the line and never notice the difference. I'm running over 200 feet of RG-6 that is grounded through a bulkhead connector at the base of the tower, another at the bulkhead where it comes into the house, two connectors where it goes through a lightning suppressor, and a splitter before the receiver which means two more F-connectors. Use good quality compression connectors that fit the cable you have.

For satellite and cable where the signals on the cable are strong this should be a no brainer. For OTA it depends on the signal strength. So if you are a long distance from the transmitter and the signal is marginal then the extra connectors *might* make enough difference to notice. However it's been my experience we worry too much about the added loss of connectors. If the signal is weak enough that an extra connector or two is cause for worry, then put in a good quality antenna mounted preamp. That will give enough signal you can quit worrying about connectors.

Where the signal loss is noticeable is when using multiple splitters or splitters with a large number of ports. Remember a two way divider is 3 db of loss per line. A divider with 4 output ports is down 6 db and these figures are much greater than you'd see with a single bulkhead connector. There is little loss in a properly installed connector when it comes to real world situations.

[herbdrake]

I spend a lot of time troubshooting TV and cable-modem problems professionally in homes. Almost all these problems end up being in the connections, but occassionally the problems are in the cabling itself.

First, the cable. Quad is much harder to terminate properly and has absolutly no benefit in terms of signal attenuation. The proper application for quad is in the wiring of head end equipment where one wishes to minimize signal transfer from one cable to another. Head-ends frequently have some cables with very high levels (perhaps 50 dBmV or more) and others much lower (perhaps 0 dBmV) and to keep signals from leaking from one cable to another, especially when they travel in parallel for long distances and are in a tight harness, it makes sense to use Quad. In a home, the only time you might consider quad is if you have a long run of cable and your house is next door to a TV transmitting antenna or something. Always be picky in buying cable; cable from many do-it-yourself outlets is garbage. Make sure that the cable has both an aluminum foil shield and a braided sheild. Cheap cable has only a foil shield and a few small conductors running between the sheild and jacket. If you have some extra money to spend, put the money into good standard cable rather than cheap quad.

Cable failure tends almost always to result from abuse of the cable. The biggest problem is when the cable is installed by electricians, who often use Romex staples. If you smash a cable with a staple, it will probably work fine for a year or so, but eventually the insulation flows and a huge impedance "bump" occurs. After a while, the cable is useless. If you MUST staple cables, only use staples or other devices that have a plastic constraint that does not pinch the cable.

But the great majority of trouble calls are due to connectors. The absolute worse offenders are the screw-on connectors that are in vogue in the do-it-yourself stores these days. Failure to make a secure contact with the shield is the usual result. I use Cable-Pro connectors with an internal O-ring seal and the matching radial crimping tool, but snap-and-seal connectors and their tool also have a good track record. Since the proper tools are very expensive, it would be a good idea to find somebody who has the right tools to do the connections for you. I do them for free in our system because it takes me much less time to put fitting on correctly than to have to locate the problem in a botched do-it-yourself job and fix it on a trouble call. If you are going to invest in a professional crimping tool, also purchase a stripping tool. That will ensure that the dimensions of the strip are correct for the connectors that you are using.

One detail often overlooked when crimping connectors on coax is how far the inner conductor extends past the fitting. If it is too short, it won't penetrate the female connector enough to make a connection. If it is too long, it will spread the female receptor, permanently damaging it. Always cut the center conductor so that it protrudes past the connector body only about one sixteenth of an inch.

On the question of wall plates, they are nothing more than F-81 barrels on a plastic plate. You can pay a bit more for high-frequency F-81s, but the actual difference is going to be less than 1 dB except at the extremes. If you are on a 450 or 750 MHz system, I woudn't bother with the high-frequency F81s, but cable systems sometimes go to 860 MHz or higher. Most people prefer wall plates because they make a neater installation, a wall plate addes two extra fittings, and that is two more opportunities for connector failure. My advice is to avoid the wall plate if you ignore my advice on using professional fittings and tools. Just make a hole in the wall (or use a wall plate with a hole in it) and run the wire into the room.

Finally, it is important to tighten all fittings properly. I carry a 7/16 combination wrench on my keyring so it will always be handy. NEVER use the push-on jumper cables that ship with many TV appliances.

One final note. When experiencing a TV signal problem, it can be helpful to understand the nature of the failure. If the low channels are okay and the high channels are bad, look for a cable failure (e.g., using RG-59 instead of RG-6 or RG-11). If the high channels are okay and the low channels are bad, look for a connector problem; high channels will "jump" an open inner conductor connection (capacitive coupling) far better than low channels.

[jswilke]

I ran all of my cables directly from the multiswitch to the STB's with one exception - the grounding block (you only have to ground one lead).

Please confirm...running only one grounding block for one of four multiswitch output cables will provide adequate grounding for both pairs of cables leading to two separate STB receivers (HR10 & HR20)?

Thanks, Jim

[herbdrake]

jswilke

I was addressing my remarks mainly to Cable customers, but they apply to satellite with some exceptions. Wiring between a receiver and multi-switch is in the 1-5Ghz range, and high-frequency F-81 (wall plate) connectors should definitely be used. Cable that has been swept to 5 or 10 GHz would also be worth the investment in satellite systems.

The importance of ground varies with the type of system and how vulnerable the system is to lightning or other potential surges. In the system I maintain, distribuition is by underground cable, so the danger of lightning surges is much diminished. But roof-top dish systems definitely require attention to the possibility of dangerous surges.

Grounding is generally done at the device through which the signal enters the home. That would probably be a splitter, directional coupler, or distribution amplifier if cable, but it might be a multi-switch or a diplexer if it is a home with both cable and satellite. Many times a special grounding device is used, consisting of an F-81 barrel connector(s) mounted in a ground block of some kind. If you are using a multiswitch, especially with multiple LNBs, every cable from the dish needs to be grounded, but if the multiswitch is located close to where the cables come into the house, I would think that just grounding the multiswitch itself would do the job. I would take a hint from local building codes as to the guage of the ground wire and the particulars as to how the ground connection should be established (cold water pipe or actual grounding rod).

In cable systems, one reason for requiring grounding is to prevent AC from going backwards up the cable plant, thus becomming a hazard to workers. The same applies to telephone pairs, which have grounded "protection blocks" at the point the wires come into the house. Many TV and audio systems may not have proper U-grounded outlets, especially in older homes, and can thus leak power to any coaxial cable since that thus becomes the only path to ground. Few TVs and related appliances have 3-wire plugs these days. So when a worker disconnects a cable for maintenance, he can get a shock by touching the connector coming from the house. (I've gotten zapped this way many times.) Satellite systems are subject to the same hazards, as you don't want a shock when adjusting or troubleshooting an LNB on a roof if you get between the cable and a vent pipe or something. So it is wise to take grounding seriously.

The subject of grounding brings up the issue of ground loops, which can introduce power-line "hum" both into the audio and into the video (where it appears as a slowly rolling bar or band or brightness/dimness on NTSC TV, but which is less of a problem with satellite or digital cable). But that is a whole different discussion.