New aerial set up

My aerial set up is as follows . An aerial which was suitable for sitting on top of a TV is in the loft. This was connected to a cable by way of a simple "tube" type object - the aerial plugged in one end the cable the other. This set-up fed ,via the cable , a recorder and then TV. All five channels were great but is now approx 30 yrs old.
Recently I had (professionally I thought) installed a new cable to feed two rooms . On junction one I can get One - Two - Three - good but not great - Four perfect and no five. On junction two I can get One not as good as J one - Two is about the same as J one ,Three has diagonal lines which I can tune out but then all I have is a perfect black and white,Four is near perfect and Five poor.
This,new, cable has been spliced into (I can only see the tape covering) the 30 yr old cable !! The old cable has not been used for a couple of years but it was left for emergency.
I do not wish to run new cable to junction Two but do need to use it.
I will remove all 30 yr old items (cable and aerial).
I see in Argos catalogue there are two main aerials(20 & 40) ,suitable for digital, which of these would solve my problem?
If you have read this far - thank you - I hope you can help.
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I can't fully follow your note, but what you should have is the following;
An aerial of the correct receiving group for the transmitter you intend to use, or a wideband if the signal levels are high and you don't suffer from interference from another transmitter. Ideally fitted outside, but the loft may be okay is the local signal level is high.
This aerial should be connected via double screened co-ax RG6 or ideally CT100 (NOT "low loss" cable from B&Q at 10 for 100 metres) to a splitter.
The cable should run from the splitter to each TV point directly. It should not be spurred off from another TV point, nor connected to the main cable by a taped joint. You may need to use an amplified splitter such as http://www.argos.co.uk/webapp/wcs/stores/servlet/ProductDisplay?storeId 00 1&langId=-1&catalogId01&productIde089 to maintain the signal levels to all sockets. If you ever wish to use a digital Freeview box on this installation however you may need to change this splitter amplifier it could corrupt the digital signal.
I would never recommend an Argos aerial. The 40 will be big and you may struggle to position it for good results in a loft. The 20 aerial is expensive for what it is and will only be okay if the local signal level is high.
A better bet would be to find out which transmitter you are receiving and buy the correct aerial from a local seller.
Don't forget that the final connection to the TV also needs to be from good quality cable with well fitted connectors.

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directing elements i.e. how long it is. If you can see the transmitter you won't need the expensive one. If the signal strength is poor get the longer one. A clue might be to have a look outside and see what everyone else is using.
I do not like the word splice! when dealing with these frequencies. You should use a good quality low loss cable from the aerial to feed a small distribution amplifier and then the other circuits. Each cable should be properly terminated with a co-ax plug. All the bits can be bought from MAPLIN.
Try to fix the aerial externally if you can you should get a better signal strength than from the loft.
Robin
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geoff

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All the bits can be bought from

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geoff

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