Fishing tips for finished basement without drop ceiling

I have a customer who just bought an existing house that has a basic structured wiring system installed. Unfortunately, the previous owner had the basement finished using drywall on the ceiling. Any tips on adding new cables to the system without taring up the drywall would be appreciated.

Reply to
Michael Quinlan
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Wireless

Reply to
Justin Time

Unfortunately they want to add video/coax outlets, not data. When I couldn't get there soon enough, they setup a wireless network as a temporary solution for Internet sharing. When I told them that a wired solution would not benefit them in terms of Internet connection speed, they decided to make the wireless permanent.

Is there any possibility of using the existing UTP (currently wired for telephone only) for video distribution?

Reply to
Michael Quinlan

Yes, use the phone cable as fishtape for a coax and CAT5 bundle. (sorry)

Look it the gadget catalogs for wireless video solutions.

Reply to
Al Dykes

UTP doesn't provide the shielding necessary for CATV. Not just necessary, but required by the FCC. Those video baluns are intended for baseband video.

CIAO!

Ed N.

Dmitri(Cabl> Yes you can use CAT5 cables for video distribution. The actual solution

Reply to
Ed Nielsen

You can try to use existing cables as pull strings: tie an actual pull string to the end of the cable and pull it back as far as you can, and then use the real pull string to pull both old and new cables back in place. Also, cut yourself access holes in strategic places in the ceiling. Places where you'd need to change direction of pulling, branch a cable out of a bundle etc.

Use generous amount of color matching raceway if cannot pull above the closed ceiling.

Also, since a raceway is surely bulkier than the cable it conceals, in some cases it makes sense to use just a color matching cable and hide it under (above/behind/whatever works) decorative elements like borders and baseboards.

Improvise ;-)

Reply to
Dmitri(Cabling-Design.com

Yes you can use CAT5 cables for video distribution. The actual solution will depend on whether you are going to be transmitting a high frequency TV signal or a low frequency video signal. The latter is a bit easier to implement using a pair of inexpensive baluns (one sample of video baluns is linked from this page:

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TV distribution, although possible is not without limitations - you can only send the first 50 channels or so due to high frequency attenuation profile of a CAT5 cable.

Good luck!

Reply to
Dmitri(Cabling-Design.com

The UTP wiring used on modern structured cabling system can be used to carry variopus video signals. Modern CAT5e and CA6 wiring can quite easily carry wide variety of signal with suitable adapters. The UTP can carry nicely baseband video (composite video, S-video, component video, RGB etc..), audio signals, digital audio, RF video (antenna/cable TV signals).

The secret to sending signals over UTP is to balance them well in order to limit both radiation and noise pick up. This kind of unshielded twisted pair wiring method is used in many CCTV applications nowadays to use existing in-house twisted pair wiring instead of installing new coaxial cable for the CCTV camera. For at least 20 years products have been available capable of transmitting video using UTP wire.

Video signal can be adapted to UTP wiring using a special balun transformer between BNC video connector and the wisted pair wiring. This converter converts the unbalanced audio signal to balanced signal which nicely travels through the cable. A similar transformer can be used on the other end of the cable to convert the video signal back to unbalanced format which fits to BNC connector. There are both passive solutions (balun transformers) and active converters available on the market for this application.

CAT5 cable is not great stuff for video signals, but with suitable adapters it can work well. The converter will convert the unbalanced video signal to the balanced signal that can nicely go though the twisted pair cable without picking up too much noise or radiating too much interference. The converter will also make more or less perfect impedance matching between 75 ohm video system impedance and around

100 ohm impedance of the wiring.

One of the most demanding applications on the market today is broadband video, commonly known as CATV or cable television. It carries a broad range of signals extending from 54 MHz to beyond 600 MHz (usually up to around 900 MHz). Coaxial cable (RG-59 or RG-6) is commonly used for these applications. There are also some products for running broadband RF video through CAT5 or better twisted pair wiring. The solution is to use a small transformer to convert from an unbalanced to a balanced signal on the sending end and and vice-versa on the receiving end. Baluns also make the necessary impedance transformation between coaxial cable (75 ohms) and twisted pair wiring (100 ohms). The use of CAT 5 for wireband RF video has been pretty limited because of quite high attenuation, especially at higher frequencies. The standard specifies attenuation of 24 dB per 100 meters of CAT5 cable, and when frequencies go higher, the attenuation increases quicly. But the higher quality cables, like CAT5e and CAT6, reduce the attenuation considerably. In practice with the suitable amplifiers and suitable adapters you can run the cable TV or TV antenna RF signal succesfully from tens of meters (or up to

100 meters on good conditions) through modern UTP wiring.

Unshielded twisted pair is suitable cable to carry balanced signals (balanced audio interfaces in professional equipment), but is far from optimal for unbalanced signals (like home hifi audio interfaces with RCA connductors). To properly transfer unbalanced signal over UTP thesignals need to be balanced (there are baluns for this). If you need to carry digital audio signals, then the signals from coaxial S/PDIF interface can be treated in the same way as video signals (you can use video BNC to UTP adapters for them).

One word to the wise: not all Cat5 converters are alike. Not all of them are good and there is a quality difference. They don't all use the same technology to do the signal conversion and you need to compare which one is good enough for your application.

When transmitting audio and video signals through twisted pair wiring, use the adapters from the same manufacturer on the both ends of the cable. There are no generic standards how this kind of adapters work, so adapters from different manufacturers are most propably not compatible with each other.

Here are some links on this topic:

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Reply to
Tomi Holger Engdahl

There are also baluns on the market designed for broadband video! Modern UTP wiring can be used to carry broadband video succesfully. And also meet radioation requirements of many countries. There are companies marketing such solutions.

Some more information van be found at

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Reply to
Tomi Holger Engdahl

Broadband video (CATV) can be transmitted over UTP, absolutely. And if you are in an area where there are no local broadcast radio or television signals (I don't mean just 10 or 20 miles away, but quite a ways further than that), you'll be just fine. Anything closer than that, and you'll see multiple images on VHF locals, cross-hatch and other noise in the upper teens through lower 20s. Channels 95-97 will have loads of garbage (FM radio), and if there are broadcast UHF channels, cable channels ~65 and up will have problems. It just kind of goes along with inadequate shielding.

If a house connected to a CATV system 75 miles away from TV transmitters has ghosting on locals due to a loose connector at the pole (ingress), why would one think that there would be no ingress with UTP (which has a whole lot less shielding than a loose connector).

CIAO!

Ed

Tomi Holger Engdahl wrote:

Reply to
Ed Nielsen

Because CATV is unbalanced and thus highly susceptible to ingress whereas UTP is balanced and thus highly immune to ingress?

-Larry Jones

My brain is trying to kill me. -- Calvin

Reply to
lawrence.jones

snipped-for-privacy@ugs.com writes:

CATV signal is normally transported as unbalanced signal ovet

75 ohm cable. It can be transported through balanced medium as well if the medium has suitable characteristics (low enough high frequency attenuation, good enough shielding / balance etc.) and you have a suitable aapter to convert 75 ohm signal to that other form (match impedance and do unbalanced-balanced conversion).

In the old days (and maybe even sometimes nowadays) twinlead wire is used to transport TV antenna signals (at least at VHF frequencies). That twinlead wire is 300 ohm balanced wire pair.

75 ohm to 300 ohm balun transformers (for example Radio Shack cat. #'s 15-1140 and 15-1253 or MCM #33-050 and #33-010) are use when this kind of cable needs to be connected to something that uses 75 ohm coaxial interface (modern equipment, cable TV network etc..)

In the same way 100 ohms UTP wiring can be used to carry antenna signal in the balanced format. All you need is low ernough loss cable (CAT5 for short distances, CAT5e and CAT6 have lower losses) and suitable 75 ohm to 100 ohm balun adapter. The CAT5 or higher UTP wiring can carry RF signals quite well. The wires are quite near each other, tightly twisted together and reasonably well balanced (very similar resistances and capacitances), which means that properly balanced signal does not leak out mich from the cable and the cable is not easy to pick up interference (if you try to push unbalanced signal directly to UTP those "shielding" properties of balanced pair are lost, meaning cable will radiate considerable amount of RF signal out and pick up RFI noise from outside sources considerably). The loss of the typical CAT5 cable is considerably higher that with the cables orginally designed to carry RF signals (RG6 coax, RG59 coax, twinlead), but still in range that it can be used to carry antenna signal tens of meters, 100 meters might be too much for highest frequencies to be useable anymore. So for cable TV connection you need a sutiable 75 ohm to 100 ohm balun converter. Here is one product that claims to do the needed conversion:

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"VideoEase CATV Balun allows traditional 75-ohm coaxial cable to be replaced by one-pair Unshielded Twisted Pair (UTP) in the CATV, VHF and FM environments in certain applications."

Reply to
Tomi Holger Engdahl

Thanks for giving me another fine example of theory that doesn't work.

I bought a couple of video baluns. The description reads:

FEATURES & SPECIFICATION ? Allows traditional 75 ohm coaxial cable to be replaced by one-pair UTP in the CATV, VHF and FM video signal. ? Saves extra cost of expensive and space-consuming coax cable and connects RF video equipment to TV, monitors, etc shortly. ? 100% tested for reliability & durability to quarantee signal integrity. ? Command Rejection: -20dB or higher at 40-500MHz. ? Insertion Loss: CATV channels 2-61 .

Perhaps one of these days soon I'll pull out my SLM and check the linearity of that portion of the system, though I'm not expecting much positive from that, either.

CIAO!

Ed N.

snipped-for-privacy@ugs.com wrote:

Reply to
Ed Nielsen

I don't know much about antenna but you can easily boost signals of it.

Reply to
bony ginhy

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