OK to amplify and split Freeview aerial twice?

[IT Troll]

I have a newly installed Freeview aerial which is connected to an amplifier/splitter in the loft which distributes the signal to 5 rooms. In one of these rooms I need to split the signal again to three separate tuners (1 TV and 2 PC cards).

Should I use an amplified or passive splitter in this room? I have read that over amplifying a signal can be bad, but equally, so can a three-way passive split.

[JayCee]

You'b be best just to try the passive method first...as they say...suck it and see.

Originally Posted by IT Troll

I have a newly installed Freeview aerial which is connected to an amplifier/splitter in the loft which distributes the signal to 5 rooms. In one of these rooms I need to split the signal again to three separate tuners (1 TV and 2 PC cards).

Should I use an amplified or passive splitter in this room? I have read that over amplifying a signal can be bad, but equally, so can a three-way passive split.

Amplifiers amplify noise and signal. If it works ok without then save your money.

[IT Troll]

Thanks for the replies, I guess I'll have to suck it and see.

The amplified splitter I was looking at also has a tetra filter and spike/surge protection. Are these worthwhile features to have anyway considering I will be connecting to £2K of equipment?

With regards to a passive splitter, is there any difference between a white plastic "consumer" one and a metal "professional" one?

[SamRadford]

Yes, the metal one is made of metal.
Which means it's fully shielded, apart from other considerations. Maybe it has lower losses.

Do you need amplification? (You'd have to measure your signal level or fit an attenuator to find out).

Do you need a TETRA filter or spike/surge protection?

If you don't, then there's no point in paying extra.

[IT Troll]

Originally Posted by SamRadford

Yes, the metal one is made of metal.
Which means it's fully shielded, apart from other considerations. Maybe it has lower losses.

They all say low loss, but then they would. They wouldn't sell many high loss splitters. Will being fully shielded make any practical difference?

Originally Posted by SamRadford

Do you need amplification? (You'd have to measure your signal level or fit an attenuator to find out).

I have tested my unsplit signal on my PC using ScanChannelBDA. This doesn't give a meaningful strength reading but it does report the quality as being 100%.

I will try splitting two-ways tonight and see how that affects these figures.

Originally Posted by SamRadford

Do you need a TETRA filter or spike/surge protection?

I probably don't need the Tetra filter, I don't know about the spike/surge protection that is why I asked. Are these actually useful or just a gimmick? Would they protect my equipment from an electrical storm for example?

[IT Troll]

Well I have tried splitting my signal two-ways (only have a two-way at the moment) and my strength reading has dropped between 6 and 12 points depending on the frequency e.g. from 75 to 66 at 490000KHz. The quality reading remains at 100% on all channels.

So do you think it will stand being passively split three-ways?

[SamRadford]

Well, here we go...

Originally Posted by JayCee

as they say...suck it and see.

[hog]

hi
why not just use the rf loop through on the 2 boxes then feed the pc last in the chain ??

[smedders]

Don't over-amplify the signal!!!

I live in Chesterfield and recieve freeview from the Chesterfield transmitter at about 70% quality and level. I used amplifing splitters for my analog and they worked fine. When i changed the aerial to a wideband one to recieve freeview, i connected freeview boxes to all the TVs and VCRs and DVD Recoders in the house. None of them recieved a signal due to over-amplifying the signal. I got rid of all the aerial distribution system of several amps and replaced it with passive splitters. This allowed all the recievers to pick up a signal which was a bit crappy. I installed a masthead amplifer (so 1 amp before any splitting) and i get adequate signal on all the boxes.

Ihave a total of 7 Freeview boxes/IDTVs and 2 PC cards running from the single aerial in this way

[Testbloke]

On a similair note ...
I have just ditched sky and bought one of the Philips living room PC's. MY loft aeriel runs directly into the PC TV card and the signal and picture seems good. As the PC has only one tuner, I want to use the digital tuner on the LCD to watch a different channel to the one that is being recorded. What is the best way to do this ?
So far, I have tried the basic splitter on the PC then run a half metre co-ax to the TV, PC tuner still good but TV still no good.
I tried upgrading the cheap white co-ax cables to expensive "digital" co-ax cables, signal was worse.
I tried an amplifier, but this left me with no signal at all (over amplified ?).

This is driving me a bit nuts so any help is most welcome

Kevin

[SamRadford]

Assuming a 4dB loss in the splitter (a good one), all you need is a 4dB amplifier in front of the splitter. Or use an amplified splitter. I think the lowest gain available is around 7dB so you might need a 3dB attenuator on the aerial input of each receiver.

[IT Troll]

Thought I would I would reply back on my findings. To recap, I needed to split my freeview signal to three separate tuners (1 TV and 2 PC cards) as none of these devices have RF loop through.

Using ScanChannelBDA, my direct unsplit signal reports as Strength 68, Quality 100%.

With a cheap plastic 2-way splitter the Strength dropped 58, but Quality remained at 100%.

Next I tried a "professional" KONIG 3-way splitter with F connectors. Even with just two tuners connected the signal dropped to Strength 51, Quality 90%.

So now I am using a 4-way amplified splitter with an 8dB gain. Strength is now at 80 and Quality is back to 100% (plus I now have a spare output and surge protection). No sign of any over-amping problems yet.