Splitting an Ariel signal 15 ways !!

[andy120]

I have to to second fix a job including the tv Ariel's, which I'm not normally involved in.
The lads who first fixed it were told by our boss to wire it as follows


- x 1 coax cable from the Ariel on the roof to the intake cupboard.
- Then from the intake x 1 cable to the living room of each flat ( 6 in total ) x 3 one beds and x 3 two beds
- Then from the living room point, star wire out to the bedrooms. ( so two points in the two beds and one in the 1 beds)
- meaning 15 points in total

It doesn't seem right to me that you can split an Ariel signal 15 ways with out some kind of amplifier Ect, my boss believes we can just use splitters where appropriate is this correct ? As I don't want to get caught out

 

[MDJ]

The Ariel cable comes into the intake cupboard, down from the roof, it's a block of flats. There is a landlords db installed , so could easily put one in.

Just do the best you can Andy, it is not your fault the first fix guy was a numptey mate is it?

 

[mhar]

Your losses will be 10dB for the 6 way split plus 3.5/6dB where you split in each flat, allow 4-6dB for cable losses (you have not given any idea of lengths so bit more if longish runs), 4-5dB if using wallplates and then add together totaling 27dB. You will need 77dB of good quality signal to achieve the recommended 50dB of signal given to each tv.
To run each cable to a single distribution point your splitter losses would be 15dB per leg plus the same for cable / wall plate losses so virtually no fifference.
However if you use a really good cable like ct125 from aerial to first split and then on to the split in the flat you can reduce your cable losses and introduce less noise, coupled with using an 'f' type wall plate and leaving a decent f to coax lead at each point to stop the customer using crap flyleads, you can lower your cable losses significantly whilst retaining quality. Most digital tv tuners will work on low signal levels as long as the quality is good.
Whilst not that common, it is achievable to have 16 points from an unamplified tv distribution system and the system.
Trouble is that in a single dwelling anything sending anything nasty down the cable is 'in house' so easy to sort. For flats it is best to use taps of the appropriate value to supply the required signal to each flats splitting point which really needs to done by an aerial installer