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home tv distribution

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bogdanfirst

New Member
ok so i face a problem.....
i need to design a tv signal distribution for my house. there will be about 5 or 6 tvs and tv tunners...
the cable comes from the tv network and it will go trough an amplifier and then it needs to be distributed. and here comes my problem. how do i do this?
do i need to have a single splitter with 5 outputs and from there to go to each tv, or can i do like this: have a 2 output spliter and one of them goes to one tv and the other output goes to another siplitter and here it siplits and so on......?
wich is the best solution?
 

stevez

Active Member
Bogdan - I've seen it done both ways but the best choice might be determined by the system losses, cost, etc.

In a passive splitter there is some loss and I suspect that some splitters are lossier than others. The cable is the same way - some cables are lossier than others. Usually the least lossy cable is also the most expensive. If the data on the loss for the splitter(s) and the cable(s) were available you might sketch up some configurations to see how multiple splitters compare to a single splitter and different cable lengths. You might have to do the calcs for several ranges of frequencies as losses are usually frequency dependent. The good part is that the loss data is usually in dB - so you can add/subtract. In a small house with short runs of cable this might be more work that necessary. In a large house with exceptionally long runs (because of access) it might be worth some design and planning effort.

A couple of things that I've learned. Amplifying a good, noise free signal before sending it on it's way down a long run is likely to produce better results than trying to amplify a weak signal at the end of the run because the amplifier will also have to amplify the noise. That's why preamplifiers for TV or other VHF/UHF work are mounted at the antenna. Leakage from the cable is less of a problem than leakage into it. If there is a path for a strong local signal from a station to get into the cable, even a little bit of it, the result will be a ghost if the network frequency is the same as the local frequency. That's how the local cable guys in my area find leaks - customers complain of ghosts on the local channels long before there are interference problems.

I hope I've made some sense and this is of some help.
 

Sebi

Active Member
The commercial splitter outputs give same signal level. In this case the best solution one splitter with 5 outputs. Also possible to build two direction with one two-way splitter, and place each cable-end 1-1 3-way splitter. If no need 6 outputs, the unused output need a 75ohm resistor to avoid the reflections(ghost-pic).
I hope with amplifier You can compensate the losses of splitters.
 

bogdanfirst

New Member
hello guys!
thanks for your replies!
basicly i can see the wiring in 3 forms.
1. a single spliter, but i will have quite a large amount of cable running trough the house and this is too annoying.
2. i have one splitter near the amp and one on each floor
3. the signal travells from splitter to splitter
4. quite similar to 3
and another way comes in my mind now....
similar to 2, but i have a 3 way splitter on one floor and a 3 way splitter on the other floor.
hope someone can give me some tips on this.
personally, i preffer 2.
 

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bogdanfirst

New Member
hm.....
yes, the second is the one that splies the same output....
though i have seen networks at the counriside done like 3, but the cable runs for miles.
i mean it splits in 2 at each user....one outputs goes on, and the other goes to that used...
so what shoud the disadvantages of the other will be?
 

bogdanfirst

New Member
ok. i understand now.....
10X!
so the idea is to have the same level of signal at all the outputs.
do you think that there is a website that can explain this in more details...
i did some searches, but i really don't even know what keywords to use....

thanks again!
 

Dean Huster

Well-Known Member
Amplifiers

You might be wasting money on an amplifier. If you start with a strong signal, the amp can boost it up so much that it overloads the tuners. Been there, done that. If you know that the splitter will kill the signal so much that the amp can decently compensate for it, then use it, but only if needed. Don't forget that a lot of amplifiers are made for terrestrial TV and may not have the upper end for cable.

Dean
 

seeker

New Member
Hi to all,

Hi bogdan first, if I were setting up 5-6 TVs I think I would get a fairly expensive 8 way distribution amp with input/output level and maybe output tilt also. Reasons why:

1: ease of setup,no splitters (except at TV VCR maybe), 5 TVs, 5 cables...6 TVs, 6 cables. With an 8 way you got 2 spares.

2: ease of maintenance; got a problem? You got 1 tv, 1 cable, plug it in to a spare output on the amp and you only have 2 other possible faults.

3: expense; spending money on a decent 8-port amp might be high at the start but if you consider your hours of time to run cable to splitters, run cable from splitters to other splitters, going back to balance splitter loads or finding a bad splitter or connection (no offense if you install your own F connectors:), then the up-front cost is very small to insure a simple,low part-count, easy-to-fix-if-it-breaks, system.

This is the way I would do it if it was my house and it's just my 2 cents.

Good luck with your project!
 

bogdanfirst

New Member
ok. i agree the simple 8 output amp is the best solution ........BUT!
i can't have all that number of cables running trougm my house. the amp will be at the 3rd floor, the attic, but no TV's are there. then on the second floor i will have 3 tv's for sure. and on the first floor, 1 or 2 or 3.....depends.
running that much of cables trough the hous will be very annoing......if you can imagine that. i know this should be the best way..and the most efficient.
but i think that the other good idea is to use a 2 way splitter, and then a 3 way for each floor. this way seems best because the number of cables that need to be run. i only need one cable from floor to floor.
also, i don't mind wasting a few hours for running the cables.
also, Dean, you say that the amp can overload.......nope! i got 2 tv's for now, with just a splitter, no amp, and there is a lost of quality if i connect both, than if i were to jusct connect one tv with no splitter.
thanks for the help!
hope someone has some other suggestions, because i need to choose the best way.
 

Gene

New Member
I vote for #1. balanced output, highest attenuation per output, and fewest splitters (allow a 1-3 dB loss at each one your signal passes through).
 

pebe

Member
bogdanfirst said:
ok. i agree the simple 8 output amp is the best solution ........BUT!
i can't have all that number of cables running trougm my house. the amp will be at the 3rd floor, the attic, but no TV's are there. then on the second floor i will have 3 tv's for sure. and on the first floor, 1 or 2 or 3.....depends.
running that much of cables trough the hous will be very annoing......if you can imagine that. i know this should be the best way..and the most efficient.
but i think that the other good idea is to use a 2 way splitter, and then a 3 way for each floor. this way seems best because the number of cables that need to be run. i only need one cable from floor to floor.
also, i don't mind wasting a few hours for running the cables.
also, Dean, you say that the amp can overload.......nope! i got 2 tv's for now, with just a splitter, no amp, and there is a lost of quality if i connect both, than if i were to jusct connect one tv with no splitter.
thanks for the help!
hope someone has some other suggestions, because i need to choose the best way.
Your easiest method is as Seeker suggests. This is a 'star' splitter and it has all signals levels equal. With a hybrid transformer split there will be a loss to each leg of approx 12dB.

Cable TV companies use a 'tree & branch' system of feeds. A single cable carries the 'tees' which divert a small part of the signal through the tee to the subscriber. The tees are graded in 'side loss' depending on the strength of signal on the main cable at that point, and each tee has an 'insersion' loss which depends on its side loss. While this system would be OK for you, the tees tend to be a specialist item normally only generally available to cable TV companies or distribution systems installers and you would have to enquire around for catalogues and suppliers.

If you want to make a system as you suggest, then make it out of readily available 2way splitters, cascaded as necessary. A splitter will give you a feed to each of the two floors, and in each feed put a 2way splitter feeding 2 more to give 4 outlets per floor. So 7 splitters are required.

Use hybrid transformer types. These give a good 75ohm match even if one leg is not connected. The insersion loss from input to each of the 2 outlets is about 4dB, so the amp needs a 12dB gain for unity gain overall.
 

mozikluv

New Member
splitting cable tv signals

:) hi! have you considered transmitting your cable tv signal instead of using cables running all over your house? i have the circuit design for this, but i have to look for it in my files, if you are interested pls. say so. :)

p.s. i have not tried this set-up but i believe this could help you out.
 

mozikluv

New Member
tv signal distribution

:oops: pls. accept my apologies about my suggestion on transmitting the the tv signal. after browsing thru my files i have found that the circuit was designed for VCR signal. Its a boo-boo mistake, again my apologies. :cry:
 
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