Sat Cable/TV aerial cable

construct06

Ok, i just want to clarify something.

I have asked this before and have read a few thread regarding same but am still a bit confused. I know some of the solutions might not give 100% clear picture, but even if i got pretty good reception i'd be happy. I know that the best solution is to use Ct-100 and go direct from dish to box. But sometimes you'll have to appreciate it is not possible, especially in an existing finished house.

Q1. Can Satellite cable from dish be joined to TV aerial cable, and this aerial cable then plugged into back of sky digibox? If so what type of joiner should be used?

Q2. How do those Tv Links work.?

TheDriver

I have WF100 coming from dish into attic where aerial exists also. I combine these using a sat/terrestrial combiner and sends it down cable that builder fitted, nasty cheap sat cable. The signal then splits at wallplate in sitting room and 2 wires, 1 to sat box, one to tv. This is needed as sat box sends power up to dish. I don't really see any loss in picture.
You could have box in attic and then just combine box output with aerial which are just 2 r/f signals combined and use magic eye but someone else would give you better advice on that.

Trevord

Concerning OP..........

Q1.

Not if the "TV cable" doesn't carry power to the LNB. Some varieties of "TV cable" are really satellite/Digital NTL/Chorus type cable (good news) as opposed to coaxial cable (bad news).

If the cable name is not printed on it you could test it by attaching sat box to tv cable and attaching a satfinder at the other end. If the cable powers the sat finder then it may be of suitable quality to carry power to lnb and thus give you a signal when everything is connected.

F connectors and barrel joiners are recommended for joining cables.

cast_iron

Trevord wrote:

Not if the "TV cable" doesn't carry power to the LNB. Some varieties of "TV cable" are really satellite/Digital NTL/Chorus type cable (good news) as opposed to coaxial cable (bad news).

I've never come across "tv cable" that doesn't allow the power through (Wall plates may block, coax cable doesn't).

As long as the run isn't too long you'll have no problem joining the cable a couple of times.

construct06

i think it may be coax cable running from attic to tv point in rooms below. whats difference between the cables (sat cable and coax cable) why wont a signal pass thru' the coax cable.

Is there any links to photos of both to illustrate the difference?

thx

Zaphod

You cannot use 'TV coax' for satellite if the coax is also shared with other tv outlets*. This is because the satellite receiver sends out a few milliamps of current to power the LNBF - if this also ends up going into the back of your tv, then you can expect fireworks.

A single, unshared run of coax (or mixed CT100 and TV coax joined together) from the LNBF to the receiver might work OK for satellite reception, but you will see a drop in signal quality. So weaker channels may be lost and in rain a lot of channels may become unwatchable. If the coax is very poor quality, you might have very few channels even in dry weather.


*Satellite and TV can share coax when a diplexer is used, which blocks current flow into the TV, but the performance will be terrible with 'TV coax' if used in place of recommended CT100.



Top 2 cables are CT100 type. Bottom one is 'TV coax'.

construct06

excellent response.

thank u, that explains everything i've been wondering about.

cheers

JoeA3

I asked a similar question to this last week.
My parents have a similar issue, i.e. an old house, really crap old coax cable running from attic to living room.
The sky installer connected the cable from the dish to the old coax in the attic, and all the Sky channels work perfectly. Signal strength/quality readings are very good. All this with really old rubbish coax cable running from a connection in the attic.

The only issue is the previously working terrestrial channels (combined with NTL before sky) no longer work...

TheDriver

Would it be possible to put all this information into a sticky seeing as its same question being asked repeatedly and in fairness to the posters, the threads can be gone by the next person wanting same info.

watty

JoeA3 wrote:

I asked a similar question to this last week.
My parents have a similar issue, i.e. an old house, really crap old coax cable running from attic to living room.
The sky installer connected the cable from the dish to the old coax in the attic, and all the Sky channels work perfectly. Signal strength/quality readings are very good. All this with really old rubbish coax cable running from a connection in the attic.

The only issue is the previously working terrestrial channels (combined with NTL before sky) no longer work...

It needs to go on the ICDGopedia

Arrrrgh!

Why do they do this!!!
The poorly screened cable RADIATES (transmits) interference from 950MHz to 2100MHz at least!

Run a separate coax, even outside. Reconnect your TV aerial.

TheDriver

Since I started looking at this board, it has shocked me how much variance there is in satellite installers namely sky ones. There are certainly talented installers out there including our own mods etc but sounds like lots of cowboys doing the rounds also. We should nearly start a rogues photo gallery (obviously not mentioning names). I really love Sky's recommendation not to install up on chimney yet lots of people around having them on poles and chimneys etc!

construct06

ya, good idea about stick or icdgopedia.

its a common question.

maybe could be appended to a Faq.