Old NTL Cable upgraded today - questions questions

BenEadir

Hi all.

My house was finally upgraded today from the old NTL cable to the new super duper broadband carrying cable.

The incoming signal when connected directly to my old PACE DVB (or is it DV3?) grey digital box is showing a steady score of +/- 34 on line 5 of the Technical Information analysis when "help" is pressed on the remote and line 4 is a steady 0.0E 00 - 0.0E 00.

When I route the cable through a 6 way splitter with a total of 4 cables coming out of it the main TV which was showing the above scores now move around between 30 and 31 and the line 4 scores hop all over the place and there is some stuttering/blocking of the picture.

The other thing I've noticed is that the other three TV's which were just running off an analogue signal (and still are) have terrible picture quality ranging from very very snowy to no reception at all.

So, the old cable has been upgraded, connected and confirmed working by the engineer and now I have a crap signal via the digital box on my main TV and unwatchable signals on the other 3 TV's. WTF??? I thought this super super cable was going to deliver picture perfect reception.

Am I missing something here? I checked all the connections to the splitter etc and they are all 100%.

Anyone got any ideas? Do I need to get a new sort of digital box? Do I need one for each room? Is the new cable not supposed to deliver analogue?

Help!!

Ben

zilog_jones

Is this 6-way splitter amplified? If not the signal loss is probably too great, I can't see how you were getting a decent signal with this before.

BenEadir

Hi Zilog,

Thanks for the reply. The same splitter was indeed delivering a very acceptable analogue signal around the house previously but if you think an amplified splitter is required with the new cable what make/model would you recommend and where's the best place to buy? I'm happy to buy online or from Peats/Curry's etc.

Ben

zilog_jones

There must have been something wrong before they did the upgrades - I'm not certain but it doesn't sound normal that a 6-way splitter would give an acceptable signal - anyone in the area not using a splitter must have been getting a terrible overamplified signal or something.

I can't recommend any distribution amp in particular (I just have a 3 way splitter here), but beware that most the stuff from the UK or in UK shops is only designed for UHF and maybe VHF Band I-III if you're lucky - not cable frequencies ("superband", "hyperband" or whatever - analogue cable goes up to about 460 MHz here in Limerick anyway).

BenEadir

Thanks Zilog,

I'll see if I can find the right type of distribution amp and see if that imporves things. I re-tuned one of the analogue tv's today and no improvement still 80% snow and 20% picture :mad: The digital box TV looks good though

Ben

BostonB

How does the splitter degrade the signal?

zilog_jones

Insertion loss
Any sort of splitter will attenuate the signal, and this increases with the amount it splits it by. Insertion loss on 6-way splitters (decent F connector shielded splitters) is typically around 10 dB. Poor quality co-ax will cause further attenuation.

BostonB

How do NTL avoid this when they split the line, when doing multiroom.

I assume it doesn't effect digital only analogue?

Incidentally my experience lately its that UPC are feeding the analogue from a poor digital signal. PQ is quite poor.

zilog_jones

When doing installations themselves, UPC would use as many connections as possible from the tap outside the house - I believe there are usually 2 per house, or more. At a guess I'd say each tap connection is good for 3 or 4 TV points, but probably not for 6. I don't know what their policy is for number of TV points they'll connect, if they have any.

It does affect digital as well, it is just in BenEadir's case the signal strength is sufficient for digital but not for analogue.

UPC do use digital sources for their analogue cable these days outside of the Irish terrestrial channels - they have no other option really. Here it looks like they're getting it off MMDS or something though as it does look a bit crap (I've occasionally seen the OSD from the Sagem MMDS boxes) - God knows why.