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If it was used for high speed internet service it is likely RG6. They need better signal strength for high speed internet over coax than analog TV.
 

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timmy1, With compression connectors you need to use a compression tool, not a crimp tool. Home Depot sells two different models of compression tools by Ideal. I have the cheaper one and it works very well.

If you are using the correct tool, double check that you are using quad shield cable with your quad shield connectors. Quad shield cable has 4 layers of shield (2 layers of foil and 2 layers of braid alternating, i.e. foil, braid, foil, braid). If you only have dual shield RG6 you need to use dual shield connectors.

When used properly, compression connectors should provide a very reliable connection.
 

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My guess is that it is an alignment issue. You have to make sure that the connector is lined up so that the centre core slides into the centre of the connector. Don't push too hard (at least not until you are sure that it is aligned properly). You then need to push the connector on so that the centre core is flush with the back of the connector (your second picture shows it back quite a bit). Only then should you compress the connector. I hope this helps.
 

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Some RG-6 comes with a "messenger wire" that is stiff wire bonded to the outside of the coax. This type is not as flexible as standard RG-6 but some people use it to have a chassis ground on all their linked OTA gear, including the ATSC tuners/TV sets. It is not suitable for lightning protection or proper grounding, it just establishes a steady 0V to drain off any static electricity buildup.
Correct me if I am wrong, but isn't that "messenger wire" actually for telephone pole mounting to take the strain off of the conductors when stretched from pole to pole?
 

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I did the first two connections, both feel sound, both felt quite tight as I squeezed the tool, but I am not getting any signal through them when I connect the TV.
The most common problem is a strand of the shield is touching the centre wire causing the cable to short out. You have to be very careful to make sure every strand is folded back before putting on the connector.
 

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The signal should take the path of least resistance on the "skin" of the conductor anyways right?
That is true, but not because it is the path of least resistance. AC signals tend to travel on the outer skin of a conductor. This is called Skin Effect. Very little of the signal will travel through the steel core, it is used for strength and cost savings. There is very little performance benefit of solid copper. Its primary advantage is flexibility.
 

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Nonetheless numerous manufacturers offer "RG-59" with foam dielectric,
different velocity factors and even multiple shields....go figure, seems to
me they should be labeled as some variation of RG-6....or something else....
While RG-x originally was a Military Spec it is now quite generic and is commonly used to specify a cable with a certain characteristic impedance and centre conductor gauge. The velocity factor, material used for the dielectric and the number of shields can vary and thus need to be specified. Theoretically you could have single shield RG-6 or quad shield RG-59 but I can't imagine either being of much use.

FYI, RG-59 has 20 AWG, RG-6 has 18 AWG and RG-11 has 14 AWG centre conductors. They all have characteristic impedances of 75 ohms.
 

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Yes, there is better cable, if you really need that last 1/10th of a dB, for 3 times the price
The law of diminishing returns really comes into play here. I would stay away from cheap cable that may not conform to specs, but any good quality RG6 cable from a reputable manufacturer should be fine. As others have said here before, with regards to signal transmission, there is practically no difference between copper clad and solid copper core as well as between double and quad shield.
 

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I bow to Deca's expertise, but I thought I would throw in my 2 cents. There are basically three grades of cable (indoor, plenum and outdoor). As stampeder said, plenum grade cable is designed for use inside HVAC systems thus can handle larger temperature extremes then indoor cable (and possibly higher temperatures than outdoor cable) but it isn't designed to handle weather (UV, rain, snow, ice, salt fog, etc.). Outdoor cable is required for that.

Most home users only need to worry about indoor and outdoor cable. Plenum grade is more commonly used in office/commercial environments and would only be needed in your home if you are dragging wires through hot air pipes (cold air returns should be OK with indoor cable).
 

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Isn't solid copper preferred when a pre-amp is used with a lengthy cable run? I always thought that was the case?
I hadn't thought about that, but I guess if you had a very long piece of coax between your power injector and your pre-amp, the DC voltage drop through steel core cable (skin effect does not affect DC power) could result in the pre-amp not working properly. There are several factors that you would have to take into account when calculating this:
  • The (DC) resistance of the coax,
  • the voltage output of the power injector, and
  • the minimum voltage the pre-amp needs.
Obviously this will vary from pre-amp to pre-amp, so there won't be a rule of thumb you can use, but I doubt if the average person needs to worry about this.
 

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One thing I've found to help run wires through cold air returns is a small "super rubber" ball. The one the kids get that really bounce. Just put a hole through it, tie a string to it, and throw it through the cold air return. It will bounce around the corners in the duct work very easily.
That is a great idea! I will have to give it a try sometime.
 

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I tend to agree with mlord. The primary purpose of the wires crossing in a bowtie antenna is phase matching. Since they have a centre feed, the current is traveling through the upper and lower feed lines in opposite directions, so any EMI induced by one will largely be canceled by the other so twisting isn't as impotent in this case. Only when the interference is coming at an angle (vertically), will twisting help, but you would probably want more than half a twist on each feedline,
 

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Got a wobbly connector on an RG6 right on the cable that runs in between antenna and preamp (preamp end at UHF input). Not sure how critical this is though.
The cable between the antenna and pre-amp is the most important one as you are dealing with unamplified signals so losses become very significant. If you don't feel comfortable replacing the connector, buy a good quality new cable.
 

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that faulty cable connector being between the antenna and pre-amp could cause insufficient voltage getting up to your preamp
Err, no. That would only be if it was between the power injector and the pre-amp. The pre-amp won't pass the voltage on the antenna, since the antenna won't care if it sees the voltage.
 

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In the user's manual, it says to mount the power supply as close to the TV as possible.
I really don't know why they say this. I suspect their technical writer misinterpreted what the engineer told him. The reality is the power injector can be anywhere between the pre-amp and the TV. Often you put it near the TV as you have power there, but you could also put it at the distribution panel if you are serving multiple TVs. In this case, this is actually preferred as most splitters will block the power.

This is the wrong thread to be talking about pre-amps and signal overload though, but I do agree with ota_canuck and you usually want the pre-amp as close to the antenna as possible. My suggestion is to fix the bad connection (preferably with a compression tool, but a crimp tool is OK). Most home improvement and electronic parts stores will sell the crimp tool, but only a few sell the compression one. Once that is done, we can talk about your pre-amp in the Signal Amplifiers (Amps, Preamps, Distro Amps) thread.
 

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Hmm, so you need actually two tools?
You need a coax cable stripper and either a crimp or compression tool (depending if you use crimp on or compression connectors). Many (myself included) prefer compression connectors.

Is there one that does both?
Both? Strip and crimp or compress? Maybe, but not that I know of.

Can I use the connectors that came with my pre-amp?
Connectors came with your pre-amp? Never heard of that before.
 

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I totally agree with stampeder and quad shield is only necessary when you are very close to a large source of interference (for example within a few km of a broadcast tower or maybe under high tension power lines).

As for the difference between the two types of Coleman dual-shield cable, I wouldn't worry about it. What Eug has is far better than RG-59 so the description of "minimal shielding" is marketing low-balling to hype their better stuff. If you have to buy more and if they are priced similarly, then you might as well get the better stuff, but I wouldn't replace what you have.

Regarding concerns about about analog cable, don't worry about it. Analog channels largely use VHF, mid-band, and super-band all of which RG-59 is good enough for, though RG-6 is a bit better so it is still recommended (it also helps with the analog channels on the lower hyper-band). It is when you get up to the upper hyper-band channels (typically only used by digital cable and internet) that you need to start to be more concerned, but even then, any good RG-6 cable is good enough.
 
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