multiple rf modulation question

gives a bite baby

Hi guys

I want to set up multiple set top boxes (Sky.upc, fta , saorview etc...) in my business.
I then plan to show all boxes on multiple tv sets ie. With modulators and coax to aeriel in to the tv's.

Would someone here know or have a link to how the best way to go about this without inference ?

Tony

Before doing anything I'd check the commercial costs of displaying sky and UPC in a business as commercial subscriptions are very expensive. Also rather than using RF distribution you could look at HDMI or cat 5/6 to preserve the HD quality.

gives a bite baby

Tony wrote: »

Before doing anything I'd check the commercial costs of displaying sky and UPC in a business as commercial subscriptions are very expensive. Also rather than using RF distribution you could look at HDMI or cat 5/6 to preserve the HD quality.

Thanks for the reply.

I know the costs associated with the services I will be putting in I should of said it will be either sky or upc along with the other free to air and some others I'm looking into.

Also the building is wired with coax rg 6 cable to the a distribution point in the building so it is all that can be used.

Tony

In that case all you need is a good quality UHF distribution amplifier and possibly modulators for any boxes you use that do not have RF out such as freesat.

gives a bite baby

Tony wrote: »

In that case all you need is a good quality UHF distribution amplifier and possibly modulators for any boxes you use that do not have RF out such as freesat.

Can you recommend a modulator ?
I think there will be at least 6 needed as I will be getting at least 4 stbs from upc / sky and the others then as well.

Can I loop all the modulators with the final one going to the amp an then out to all the tv's ?

winston_1

gives a bite baby wrote: »

Can you recommend a modulator ?

Analogue or digital?

St Senan

gives a bite baby wrote: »

Hi guys

I want to set up multiple set top boxes (Sky.upc, fta , saorview etc...) in my business.
I then plan to show all boxes on multiple tv sets ie. With modulators and coax to aeriel in to the tv's.

Would someone here know or have a link to how the best way to go about this without inference ?

No disrespect OP but for what your wanting to do you should contact a well known local legit installer in your area/town. There are guys who for a living specialize in what you are trying to do and who also could recommend different ideas and equipment to you.

byte

You could buy basic FTA boxes with modulators built in already. Technomate TM5200 comes to mind, though there are cheaper things, like the Triax SR100, etc.

There are also a few DVB-T boxes with modulator -I know there's a Strong one anyway, don't know model though.

As with any of the basic FTA boxes, they don't retune themselves should channels change frequency or whatever, but grand otherwise.

Also, no to looping modulators together.

watty

Talk to Polytron if they are still in business. You need "professional" CATV distribution Modulators if you want more than maybe 2 modulators on one cable. Signal levels must be balanced, which can mean up to x2 or x4 on higher channels if cables long.

You need also "cable TV" rated distribution amplifier/splitters for more than about 4 channels.

Built in modulators are poor and noisy and built down to a price just for a single local TV really. You need separate Modulators and not the kind Maplin sell (it's just the kind in a setbox).

Cheap modulators (and ALL built in models in setboxes, game consoles etc) use up at least 2 channels (one adjacent to selected channel) and often interfere on two higher ones.

Byte is right. The noise and interference is horrible looping modulators. Distribution systems use a combiner (passive splitter in reverse).

bulbs2010

I done a hotel recently with 4 saorview boxes and and 4 technomate , I looped all the boxes together then into a standard distro amp ,and there has been no problems

Antenna

bulbs2010 wrote: »

I done a hotel recently with 4 saorview boxes and and 4 technomate , I looped all the boxes together then into a standard distro amp ,and there has been no problems

A problem there is if one modulator fails/looses power, it would also kill (or severely attenuate) the looptrough of the modulators prior to it in the chain. So instead of just one channel failing, they could all fail if its the modulator that is the last link in the chain that goes off.
This is more likely a possibility with a receiver with a built-in modulator (and the receiver dies) than an external modulator.

The best way of doing it is to combine the modulators using a combiner like seen on this page:

http://www.taylorbros.co.uk/PDF%20PAGES%20AS%20INDEX/26-29.%20WEB.pdf

these combiners will also filter out noise from the modulators that might affect other channels

watty

bulbs2010 wrote: »

I done a hotel recently with 4 saorview boxes and and 4 technomate , I looped all the boxes together then into a standard distro amp ,and there has been no problems

We don't know how good the pictures are though*. Even if it "works" for a given definition of "works" it's a pretty rubbish unprofessional solution. A combiner isn't much extra expense. Also if you need to feed a lot of TVs the distribution system needs to start with cleaner signals. Hence "properly" engineered systems use a "shelf" of proper VSB Modulators that only use one channel and are filtered. Built in Modulators have a spurious adjacent channel (double sideband) and no filtering, so noise on other channels . Taylor Bros sell proper modulators too.

If the TV at other end of building doesn't have as good a picture as a single TV plugged into only one set box via 2m cable then it's done wrong. Actually the modulators Taylor sells give a better picture than the modulators built into most set-boxes.

(*I've stayed in lots of hotels with very rubbish distribution though)

bulbs2010

watty wrote: »

We don't know how good the pictures are though*. Even if it "works" for a given definition of "works" it's a pretty rubbish unprofessional solution. A combiner isn't much extra expense. Also if you need to feed a lot of TVs the distribution system needs to start with cleaner signals. Hence "properly" engineered systems use a "shelf" of proper VSB Modulators that only use one channel and are filtered. Built in Modulators have a spurious adjacent channel (double sideband) and no filtering, so noise on other channels . Taylor Bros sell proper modulators too.

If the TV at other end of building doesn't have as good a picture as a single TV plugged into only one set box via 2m cable then it's done wrong. Actually the modulators Taylor sells give a better picture than the modulators built into most set-boxes.

(*I've stayed in lots of hotels with very rubbish distribution though)

"rubish and unprofessional" Watty the reception is crystal clear in every room if it works it works .I looped the boxes just to see what it would be like and to my suprise with a little bit of tweeking it was perfect now I dont know why you call that unprofessional .I find people can sometimes overcomplicate things.

watty

1000+ pixel Photos of each channel? TV picture filling width of frame. Of 4 different TVs. Even then how do we know it's photos of what you describe?

If truly it's perfect then you are very lucky. It would be very unusual.

Even so just because a really badly done solution "works" (we have only one claim vs plenty of evidence it doesn't work properly) it's no reason to recommend it publicly.

bulbs2010

you want me to take pictures of the tv,s?I have not been in there in ages the last time was when rte changed frequencys and they were all ok then but I will the next time im in there ,hopefully that will be when the years guarentee is up .I am not recomending it as a professional solution but it is worth giving it a try ,ps I used to work with chorus and I done alot of work in professional head ends so I do know what im talking about