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Thanks for the photo, timmy1: I think I see the problem here. The copper core wire and the stripped white portion of the coax are too long.

Do you have a coax stripping tool? If not, definitely get one so that you get a standard, correct measurement every time. Get a good one that allows you to set the depth of cut of the knives with an Allen wrench. That way you can set them very precisely.

In the case of the photo, even if your compression tool actually made it fit, the problem is that every time you would screw in that coax end onto a female fitting the threaded nut portion would be pulled onto the female fitting in the inwards direction as we want, but the inner core of the coax would reach a stopping point on the female fitting at which it can no longer travel inwards, so it would act as a "pushing outwards" force opposite of the threaded portion. In that case your compression fitting would fail over a short time.
 

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Loss from adapters is there but quite low, almost immeasurable if all the fittings and coax are new, but the fewer the adapters the better. Connections will last for many years indoors. Tighten all of them just beyond finger tight with two 7/16 wrenches. If you tighten them too hard you could cause the coax core to separate from its insulation and then you'll be very unhappy. Remember: just beyond finger tight.

Outdoor connections will degrade over time and cause problems as moisture gets in, so see this thread for weatherproofing those connections:

http://www.digitalhome.ca/forum/showthread.php?t=29559

I have no personal experience with flat ribbon-style TV cables so I cannot comment on any signal loss by them.
 

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Is the Colour of Coaxial Cable significant?

I was sent a very nice email by someone who didn't want to post here because they were worried that their question was a dumb one. No, it is not a dumb question, it is a very good one! :) Folks should go ahead and post in threads here rather than email or PM me.

The question was whether the colour of a coaxial cable is significant. The answer is no, the colours are meant to just be options for the installer/consumer.

Here is one example of how I've used a few different identifiers such as RG6 colours, imprinted info, and silver or gold connectors to sort out some complex installations:
  • black Belden-brand w. silver connectors = VHF TV antenna
  • white Belden w. silver connectors = UHF TV antenna
  • white RCA-brand w. silver connectors = ExpressVu 91 dish LNB left
  • white Belden-brand w. gold connectors = ExpressVu 91 dish LNB right
  • beige Belden w. silver connectors = ExpressVu 82 dish LNB left
  • beige Generic-brand w. gold connectors = ExpressVu 82 dish LNB right
  • black Belden w. gold connectors = CATV Internet
The purpose of doing all that was so that I could tell right at the grounding blocks at the house demarc point exactly which lead went where. Any time there are similar coloured coax lines and I cannot see their connectors, I can check the imprinted info on them to tell which strand is which. I've tried to keep the same scheme inside the house but sometimes its been impossible due to inacessibilities. A person could use all the same colours for such cabling but they'd have to label each strand separately in weatherproof manner. The problem is that they cannot tell in mid-strand which cable it is if they cannot see the ends. ;)

I am a fan of Belden coaxial cable but Amphenol is a great brand too. Having said that, I've not had any problems with generic RG6 or the RCA-branded spool I once bought at Home Depot.

EDIT: Jase88 makes an interesting point later in this thread in Post #40 that white coaxial cable does not heat up in the direct sun as much as black does - good to keep that in mind for possible connection failures on hot roof tops in the summer
 

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Hi, I've merged your post into this thread that covers cabling for OTA, so have a read through it and you'll get great info.

Generally if you can buy Amphenol, Belden, Leviton, or even RCA brand RG-6 you will be very pleased with its quality and it will do fine as an antenna downlead into your home. Most people do not need "quad shield" but if you intend to run your coax cable inside or against any heating ducts you should consider "plenum" quality. You can pick some up for a reasonable price at Rona or Home Depot.

Also here is a link to the forum dealing with cables of all sorts, and you'll find some threads in which we've discussed RG-6 labels and codes:

http://www.digitalhome.ca/forum/forumdisplay.php?f=97
 

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For OTA we are only handling frequencies between 54MHz and 806MHz (and its shrinking from that in the future) so unless you are also planning to run satellite gear on the same coax then the "swept to X MHz" doesn't matter. :)

RG-6 and RG-6/U are the same thing in today's consumer market.

Quad shielding is very rarely worth the extra money. You would need to be located almost right on top of an OTA broadcast antenna farm to require quad. ;)
 

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Coaxial cable relies on its internal conductor to handle the signal. In today's consumer grade RG-6 the conductor is solid 1mm copper.

Any signal losses (about 6 dB every 100 feet) occur on that conductor. If I wrap a 100 foot length of RG-6 in additional shielding I will still have the exact same line loss of about 6dB.

The shielding is only just that - shielding. :)
 

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OTA over LAN cable & adapters?

Reply to post in the Ottawa Reception thread:
TECHNOKID said:
can anyone tell me if RJ45 through coax converters would be a viable option?
I don't know the comparison of the actual wire from twinlead to Cat5e but TV amps and tuners are sensitive to the wire's velocity and other factors so I cannot say if its a one-for-one swap.

Where something like Cat5e through RJ45s would be problematic is with interference - it would be hard to trace to a single location over a long run. There is such a thing as shielded Cat5e but its expensive and hard to work with, so I'd say just stick with coax and standard F-fittings.
 

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DarKYiNe, this table from HDTVPrimer compares the loss rates of RG-59 and RG-6, with the industrial-grade RG-11 too:



Go with RG-6 all the way if you can, especially since you're talking about an 80 to 100 foot length.
 

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You can run RG-11 anywhere, but it is overkill because RG-6 performs almost the same at smaller lengths and RG-6 is much more flexible. Crimping the ends on RG-11 also requires different tools and parts.
 

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To me quad-shield is also overkill unless you are stringing your coax through/past areas of high EMF interference, which is very rare in a typical home.

Having said that, other members have pointed out that some stores sell it as their basic RG-6 type so if the price is good I don't see any harm in it. If you are going to crimp it yourself you'll have to be careful with how you handle that extra shielding so that you don't void it or cause a short.

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.
 

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I'm thinking its probably (?) braided-core too. If so, cutting or crimping it any shorter would be a real hassle without tinning the ends with a soldering gun.

For some uses it would be great though.
 

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Shielded twinlead is actually pretty simple to use, but I take the added steps of tinning the stripped wire ends with a soldering gun so that the wire doesn't fray when torqued down under the screw terminals of the preamp or similar connector.
 

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The shielding acts like a Faraday Cage, so grounding it is not necessary. The same thing goes for the shielding in coaxial cable: even if you don't run it through a ground block the shielding still works. I don't knock anyone for grounding in these situations, but its not a showstopper if the shielded twinlead is simply going from the antenna's feed points to the preamp (length of 3 feet or less).

One other thing about your particular preamp: the weatherproof cover on those models has a slot or two for standard sized twinlead to sneak through... you'll probably need to carve the hole e a bit bigger with an exacto knife to accomodate the shielded twinlead, and then waterproof the hole.

Grounding thread:
http://www.digitalhome.ca/forum/showthread.php?t=62265

OTA Waterproofing, Sealants, Adhesives, Paint thread:
http://www.digitalhome.ca/forum/showthread.php?t=104181
 

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Is it shielded twnlead, or is it standard? Shielded is preferable and will do fine indoors. Unshielded can sometimes be a hassle with interference.

Also I'm assuming your preamp has 300ohm input, correct?
 

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Electrically, solid copper is a much better conductor than copper-clad steel core. The VP (Velocity of Propagation) ratings of coaxial cables are expressed as a percentage of the speed of light, and they are much higher with solid copper than with steel core.

Also steel core is not nearly as flexible as solid copper so it can be a hassle to hump around a building or up through tight spots. I only use solid copper RG6.
 
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