Pixelation problems

[Mr_T25]

I'm getting pixelation problems despite having excellent signal strength and 100% signal quality on my analogue TV but via my Sony Freeview PVR. I currently have a three-way Signal booster next in my main living room TV which is sending the signal 2 to 3 other bedrooms. I'm only able to check the one bedroom which is connected to the TV booster and is facing this problem as the other TVs are connected to Sky / Virgin Media.

Any suggestions on how I can resolve this?

 

[secureiam]

if you have a tv with freeview, take it and plug it in instead of your freeview box.

 

[Lucid]

It's signal overload. Quality is the most important thing. Signal strength is far less important. Boosters and powered splitters will increase signal strength and can lead to signal overload in cases such as yours where you already have excellent signal quality. People often mis-diagnose signal break-up as insufficient signal because of what they remember from the days before digital TV.

The answer is to remove the powered (active) splitter and instead replace it with a passive (unpowered) splitter. One of these will do just right for you. Alternatively you could mess around fitting either a variable or fixed-level attenuator to the signal line before your powered splitter behind the TV but it would cost just as much and you'd end up with lower quality as well as lower strength and so the signal would actually be a bit worse.

 

[Mr_T25]

That was one of my assumptions because the old 20 year old Wolseley(sp?) booster was coming apart and the new one has no variable control.

I'm not sure that not fitting s booster will work as I tried this many years ago given that we have the incoming signal split 4 ways at the booster.

 

[Lucid]

Some of what you said really doesn't make sense in the context of my initial reply to you, so I want to just try to clear up any misunderstandings both ways.

Boosters and splitters: If there's enough signal both in terms of quality and strength at the end of a bit of cable then you can split it passively. That means you can put a device on the cable that will then split the signal two, three or four ways and that that device doesn't need to be plugged in to the mains. That's what 'passive' means; no mains power required.

Passive and active splitters do the same basic job of splitting the signal but there's a couple of very important differences in how they do it. A passive splitter simply divides the signal a number of ways but without adding noise. The amount of signal (the signal STRENGTH) is reduced but the difference between the signal level and the background noise (the signal QUALITY) is maintained. This type of splitter is ideal where the signal strength is already high (S = an 8 a 9 or a 10 on your Panasonic TV) and where Q is high too.

Active splitters increase the signal strength (S) but reduce the signal quality (Q). This is because they add noise to the signal from the amplification circuit. If the strength of the signal is already very high before splitting (8-10 on the Panasonic scale) then adding the extra boost from from a powered splitter can do more harm than good.

 

[Sam Gangee]

More info here: http://www.satcure.co.uk/tech/amps.htm

 

[ericmark]

Now I am confused, I though Q was magnification factor of a tuned circuit and is the ratio of voltage across the inductor (or capacitor) to the voltage across the effective resistance of the circuit. I thought signal strength was S and we has a S meter normally showing 1 ~ 9 then plus 10 or 20 dB?

I though Q was in essence how well the tuned circuit rejected out of frequency signals and is part of the receiver or band pass filter? I seem to remember all those years ago how we aimed for the highest Q we could get?

 

[Lucid]

Now I am confused, I though Q was magnification factor of a tuned circuit .....

X isn't always a variable in an equation. Sometimes its a kiss in written communication, or if you're a pirate it's the location of the buried treasure. The context is key. We are talking here about the signal display meter on a TV (a Panasonic in this case) where S stands for Strength and Q stands for Quality. Try not to over-think things.

 

[ericmark]

I don't think I will ever get use to the new short hand, to me a CD was a plate on a car showing your a diplomat, and a PC is a police constable, even if the latter was registered by IBM as the name for their computers. And I still call it writing not texting and I still use the Q code not this LOL stuff. QSL

 

[Lucid]

Each to their own I suppose, but CD for Compact Disc and PC for Personal Computer have both been in common use for more than three and a half decades. In the context of the average human life span I think that's stretching the definition of "new".

If you haven't yet adapted to recognise these acronyms in context then that strikes me as someone trying to be obstinate for its own sake. Personally I'd view that as quite a debilitating position to take. I know that I couldn't live with taking such an inflexible approach to language.