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Dr3am

Best was to lengthen RG59 cable?

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Hi

 

I'm upgrading a system at a property that already has 16 cameras using RG59 Siamese cabling. The power supply and DVR are in 2 different locations but the video leads to the DVR need to be extended about 15 feet further than where the old CPU based DVR was located to a rack. What would be the best way to extend the wires without using the BNC barrel connections? A few times I have used those things there is always intermediate video loss. I have even tried ordering different types of barrels from different vendors with the same result. Any input would be appreciated.

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If you have room on the rack ( 1U ) then install a patch panel with panel mount double female BNC. Then make up a bunch of 15' patch cables. This will not overcome your problem with insertion loss which will remain at about 1.5dB but if this is of importance then you have other design issues to address

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well the rack is 15 feet away from where the old CPU based DVR is located now and I need to rack mount the new stand alone DVR about 15 feet away from there to the rack. If the wires where already at the rack I would not need to extend them.

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i've used barrels on dozens of jobs to extend cables, never had an issue with them. either you're using really junky barrels (or even the *wrong* barrels - make sure they're designed for 75 ohm impedence), or your terminations aren't done properly. there really is no other way to do it *properly*, short of running new cables.

 

edit: one other thought, one thing i've done on a couple occasions, when extending pc-based dvrs that use the 'whip' cables, i've used vga or dvi extensions (depending on which connector the whip uses), then just left the whips connected to the cable runs. it may or may not work depending on the actual pinouts the dvr uses, but it's worked for all the dvrs i've tried it on.

 

of course, if you're going to a standalone dvr without the whip cable, this isn't an option.

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If it was me and didn't want to deal with BNC to couple the extension to, I would just use F59 connectors and F81 barrel connectors, as I've never had an issue with them.

 

Dennis

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If it was me and didn't want to deal with BNC to couple the extension to, I would just use F59 connectors and F81 barrel connectors, as I've never had an issue with them.

 

Dennis

 

 

That sounds like a good idea. I use the F81 barrels on my satellite installs all the time with no problems. Guess ill pick up some F59 connectors.

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Great. By the way, did you feel the "shaking" the other day from the earthquake off the coast?

 

 

Nope I'm located in the most Northern part of So Cal.

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RG6 is desiged for UHF RF signals not composite cctv signals

 

 

I've used it before from the DVR spot monitor output to a LCD TV with a BNC fitting on one end and a RCA on the other to the composite input of the TV. Quality wasn't bad but do you think it will affect the picture quality of the camera's to the DVR?

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If it was me and didn't want to deal with BNC to couple the extension to, I would just use F59 connectors and F81 barrel connectors, as I've never had an issue with them.

 

Dennis

 

 

That sounds like a good idea. I use the F81 barrels on my satellite installs all the time with no problems. Guess ill pick up some F59 connectors.

there's really no *functional* difference between this and using bnc barrels; the only difference is in the procedure for terminating the cables.

 

Also what if I go from the RG-59 to RG-6 dual shield?

 

as long as both are 75 ohms, solid copper core and braided copper shield, there should be no issue. rg6 is used regularly in cctv; the main reason rg59 is preferred it that tends to be thinner, more flexible, and easier to work with.

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RG6 is desiged for UHF RF signals not composite cctv signals

 

 

I've used it before from the DVR spot monitor output to a LCD TV with a BNC fitting on one end and a RCA on the other to the composite input of the TV. Quality wasn't bad but do you think it will affect the picture quality of the camera's to the DVR?

 

Yes it works & there are probably thousands of installations using it. Howeve the design parameters are different & there are problems that can be due to using RG6. Put it this way - if you already have RG59 you will gain nothing by replacing it with RG6

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RG6 is desiged for UHF RF signals not composite cctv signals

 

 

I've used it before from the DVR spot monitor output to a LCD TV with a BNC fitting on one end and a RCA on the other to the composite input of the TV. Quality wasn't bad but do you think it will affect the picture quality of the camera's to the DVR?

 

Yes it works & there are probably thousands of installations using it. Howeve the design parameters are different & there are problems that can be due to using RG6. Put it this way - if you already have RG59 you will gain nothing by replacing it with RG6

Not true.

 

Don't confuse CATV (antenna) cable with CCTV cable. RG59 and RG6 antenna cable will not transport baseband video very far due to the high resistance of the copper-clad steel inner cable and the steel or aluminum shield.

 

RG6 (and RG11, for that matter) CCTV cables work just fine. In fact, CCTV RG6 can transport analog video approximately 50% farther than CCTV RG59 (1,500 feet vs. 1,000 feet). Examples of suitable RG6 cables are West Penn 806 and Belden 1369.

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It is not a question of signal attenuation but one of RFI rejection. RG6 uses foil tape shielding which is not all that effective below about 40Mhz

 

 

 

 

 

 

only if you buy with foil........... just like you can with RG59 ....... but not the best for cctv

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Just never be tempted to make a direct splice in the cable. I've seen some dreadful splices, some barid and conductor side by side into terminal block, some where they've soldered the center together indulated it with "chewing gum" or blue-tac , wrapped in foil paper (probably the gum wrapper) and joined the braid around the outside and wrapped again with PVC tape

DISGUSTING! Next time I'm going to take a photograph and post it to this forum.

 

Use connectors and seal with 'self amalgamating' tape or 'heat shrink tubing' or in an IP rated junction box.

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It is not a question of signal attenuation but one of RFI rejection. RG6 uses foil tape shielding which is not all that effective below about 40Mhz
Actually, it is. You can use CATV cable for very short runs (~100 feet), but for longer runs the attenuation becomes too great.

 

Loss per 100 foot examples:

 

West Penn 841 RG6/U Type CATV Coaxial Cable

Mhz db/100ft

5 .45

55 1.45

 

West Penn 806 RG6/U Type CCTV Coaxial Cable

Mhz db/100ft

1 .24

10 .52

 

Note West Penn type 806 is CCTV RG6. There are plenty of other examples of copper/copper RG6.

 

PART NUMBER: 806

DESCRIPTION: RG6/U – 1 Conductor 18 AWG Solid, 95% Bare copper braid and an overall PVC Jacket.

NEC RATING: CMR

APPROVALS: (UL) C(UL) Listed or c(ETL)us Listed

APPLICATION: Indoor for: Security Cable - CCTV

http://www.westpenn-wpw.com/pdfs/coaxial_spec_pdfs/CCTV/806.pdf

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When I say it is not a question of attenuation I'm referring to the point that I am making. Everyone is focused on the attenuation characteristics & that is it. What I'm saying is that there is other design parameters that should be considered.

Even the simplest of minds would realise that if RG6 was so much better than RG59 then RG59 would not still be made. RG6 was made for a purpose & that is UHF digital RF

I have never seen braided RG6 but then again I don't work with RG6. It would be interesting to see the specs

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When I say it is not a question of attenuation I'm referring to the point that I am making. Everyone is focused on the attenuation characteristics & that is it. What I'm saying is that there is other design parameters that should be considered.

Even the simplest of minds would realise that if RG6 was so much better than RG59 then RG59 would not still be made. RG6 was made for a purpose & that is UHF digital RF

I have never seen braided RG6 but then again I don't work with RG6. It would be interesting to see the specs

I posted them for West Penn but here they are again:

 

West Penn Type 806 RG6/U Type CCTV Coaxial Cable

Conductor 18 AWG Bare Copper

Stranding Solid

Insulation Material Gas Injected Polyethylene

Insulation Thickness .180” Nom.

Number of Conductors 1 Center Conductor

Shield 95% Bare Copper Braid + Tape Barrier

Jacket Material PVC

Overall Cable Diameter 0.270'' Nom.

Approximate Cable Weight 26 Lbs/1M' Nom.

Flame Rating UL 1666

Electrical & Environmental Properties:

Temperature Rating -20deg C to 60deg C

Max.Capacitance Between Conductors @ 1 KHz 16.2 pf/ft Nom.

Velocity of Propagation 82% Nom.

Impedance 75 ohms Nom.

DC Resistance per Conductor @ 20deg C 6.5 Ohms/1M' Nom.

Jacket Color Black

RoHS Compliant Yes

Mechanical Properties:

Max. Recommended Pull Tension 41 lbs.

Min. Bend Radius (Install) 2.5”

Mhz db/100ft

1 .24

10 .52

50 1.18

100 1.83

400 3.95

700 5.38

1000 6.45

 

Note the difference in DC resistance per 1,000 feet:

RG59: DC Resistance per Conductor @ 20deg C 10.1 Ohms/1M' Nom.

RG6: DC Resistance per Conductor @ 20deg C 6.5 Ohms/1M' Nom.

 

And no, CCTV RG6 doesn't get much use but that's due to cost. In point of fact, I used copper/copper CCTV RG6 on occasion for very long runs (>1,000 feet) but the advent of UTP, baluns and active transmitters and receivers made the additional cost and cable run requirements of CCTV RG6 not worth the effort.

 

Also contrary to your logic - it has become very uncommon to find CATV RG59 due to its attenuation characteristics at the near-GHz frequencies common in today's TV signal transport and because the cost of CATV RG6 dropped to nearly that of CATV RG59 since much more of it is being produced. Still, despite the lack of use for TV wiring, CATV RG59 is still being produced (and often sold to unsuspecting CCTV installers) but it's pretty uncommon.

 

For that matter, you can also use RG11 copper/copper for CCTV, though its cost is phenomenal:

 

West Penn 811:

DC Resistance per Conductor @ 20deg C 2.6 Ohms/1M' Nom.

Good for up to 3,000 feet. " title="Applause" />

 

Here's a West Penn CCTV Cables Technical Bulletin: http://www.westpenn-wpw.com/pdfs/coax_train.pdf

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Looking at the specs you posted I would say your example RG6 is not a generic type but a high end specialist manufacture - hence the cost.

For off the shelf generic RG6 (which is what most end users will buy) -- dB/freq per 100m

 

4.9dB @ 50Mhz

6.9dB @ 100mHz

14.4dB @ 400Mhz

19.7dB @ 1 Ghz

 

Specs for RG6 are not normally quoted under 50Mhz since it is NOT recommended to use it at the lower frequencies. Again you seem fixated on attenuation & how far the run can be.

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Specs for RG6 are not normally quoted under 50Mhz since it is NOT recommended to use it at the lower frequencies. Again you seem fixated on attenuation & how far the run can be.
And you seem fixated on CATV RG6 when it's obvious there is CCTV RG6 being manufactured by a number of companies. Other examples:

 

Windy City Wire 606111-S - http://www.smartwire.com/SpecSheet.asp?sSumPartNumber=606111

 

Belden Model 1694A - http://www.belden.com/techdatas/english/1694a.pdf

 

Commscope 5700 - http://www.commscope.com/catalog/systimax/product_details.aspx?id=25155

 

Liberty Cable RG6-CCTV-PL-BLK - https://secure.libertycable.com/prod_details.php?pitem=RG6-CCTV-PL-BLK

 

Comprehensive Cable RG6 18 AWG BC CCTV Cable Plenum - http://www.comprehensivecable.com/store/p/14705-Comprehensive-RG6-18-AWG-BC-CCTV-Cable-Plenum.html

 

Tappan Wire - http://www.tappanwire.com/product_details.php?pid=131&cid=8

 

Coleman Cable 92045 - https://www.ccixpress.com/wcsstore/CCIxpress/images/catalog/catalogPDFs/9-/92045.pdf

 

Hosiwell F-RG-6/U - http://www.hosiwell.com/coaxial-cables/RG6-for-CCTV.html

 

MCM Electronics 24-14360 - http://www.mcmelectronics.com/product/24-14360

 

Does it cost more? Certainly! For one thing, RG6 is less common for CCTV than RG59. For another, RG6 contains more copper per foot - copper is expensive! For a third thing, RG-anything has been replaced by UTP; both for IP cameras and, with baluns, for analog.

 

Nevertheless, RG6 copper/copper is available and it can transport analog CCTV farther than RG59, despite your never having seen or used it. I have used it for runs >1,000 feet, but that was over 15 years ago, before UTP baluns became popular. Today, I would not usually consider RG6 or RG11 for long runs - I would likely use UTP passive/active or active/active.

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[And no, CCTV RG6 doesn't get much use but that's due to cost. In point of fact, I used copper/copper CCTV RG6 on occasion for very long runs (>1,000 feet) but the advent of UTP, baluns and active transmitters and receivers made the additional cost and cable run requirements of CCTV RG6 not worth the effort.

 

Also contrary to your logic - it has become very uncommon to find CATV RG59 due to its attenuation characteristics at the near-GHz frequencies common in today's TV signal transport and because the cost of CATV RG6 dropped to nearly that of CATV RG59 since much more of it is being produced. Still, despite the lack of use for TV wiring, CATV RG59 is still being produced (and often sold to unsuspecting CCTV installers) but it's pretty uncommon.

 

For that matter, you can also use RG11 copper/copper for CCTV, though its cost is phenomenal:

 

 

 

 

So there we go. You can get CATV RG59 & CATV RG6 as well as CCTV RG59 & CCTV RG6.

If the RG6 is so perfect why do they make a Foil shield version & a braided shield version. What is the difference that requires both to be made. My initial point (which you seem to want to ignore) is that foil shielding is designed for higher frequencies than CCTV baseband & whilst it "can" be used it can also be the source of problems. The only advantage it offers to CCTV use is its lower attenuation .

As for using RG11 - why would you even consider it. If long runs are required then just use basic transmission engineering principles. Pre & post equalisation & amplification to requiremnts can get you a couple of kilometers for very little cost.

UTP has the problem of physical fragility ( especially at the termination points) unless it is terminated at at patch panel using standard data cabling techniques.

 

As they say - " there is the right way to do things & there are the other ways"

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So there we go. You can get CATV RG59 & CATV RG6 as well as CCTV RG59 & CCTV RG6.

If the RG6 is so perfect why do they make a Foil shield version & a braided shield version. What is the difference that requires both to be made. My initial point (which you seem to want to ignore) is that foil shielding is designed for higher frequencies than CCTV baseband & whilst it "can" be used it can also be the source of problems. The only advantage it offers to CCTV use is its lower attenuation .

As for using RG11 - why would you even consider it. If long runs are required then just use basic transmission engineering principles. Pre & post equalisation & amplification to requiremnts can get you a couple of kilometers for very little cost.

UTP has the problem of physical fragility ( especially at the termination points) unless it is terminated at at patch panel using standard data cabling techniques.

 

As they say - " there is the right way to do things & there are the other ways"

For the same reason they make many types of RG-anything. Different cables for different applications. There's antenna, CCTV, digital and other uses for RG6. Each use has its own set of requirements.

 

Don't be fixated on the shield construction. There's nothing inherently wrong with foil shielding for CCTV, but foil alone (or even foil plus 22Ga drain wire) is not enough. The point, as you steadfastly refuse to ignore, is low frequency (usually DC) resistance. For analog CCTV, which has relatively low frequency signals (25-30Hz) , DC resistance is important. Hence the requirement for solid copper center conductor and 90+% braided copper shield.

 

Foil shielding plus aluminum drain wire (or a small copper drain wire) is cheaper to produce than braided copper shielding and, for RF applications, where the "skin effect" comes into play, is perfectly sufficient. The same goes for "BCCS" (bare copper-coated steel) center conductors. The higher the frequency, the more the signal migrates to the outside of any conductor. Since copper is quite expensive, it makes sense to construct high-frequency RF cables with a minimal amount of copper to save money. Solid copper would be unnecessary.

 

Can the cable shield also contain foil? Yes, as long as it has sufficient copper in the shield to form a "return" for the signal. Your claim that foil does not block interference is untrue. It does, but foil plus a small (22GA) drain wire does not provide a low enough resistance to provide adequate return for the low frequency signals.

 

For that matter, check out some of Belden's product line. 1694 has "Duofoil® + tinned copper braid shield (95% coverage). Does the foil prevent it from use for CCTV? Absolutely not. There are specialty cables with different configurations that are perfectly acceptable for CCTV. Serial digital cable, for instance, will pass analog signals just fine, as will cables with stranded center conductors.

 

Equalization to extend cabling, especially "post", adds noise. It should be avoided whenever possible. That's not to say it can always be avoided - UTP active transmitters and receivers have equalization. In that respect, it is better to equalize the transmitter than the receiver but that option is not always possible. There aren't many applications where you can fit an active transmitter into the available space and it would be a royal pain in the a** to adjust equalization at the head end.

 

By the way, stranded UTP cable is available from a number of manufacturers - specifically for areas where the cable is subject to flexing. And for use to transport analog signals, strict adherence to Ethernet termination guidelines is not necessary. We often use Telco "beans" to splice wires with no measurable effect on the video signal quality. The key is to maintain each pair's twist as much as possible to maintain the cable's noise cancellation capabilities.

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