Another TV/aerial issue!

[Davisss]

Hi guys, sorry if this has been answered already but i couldnt find anything. On sunday i installed three aerial points in three upstairs rooms. i had a test tv which i plugged into the aerial direct and the signal strength was nearly 50% strength. It however picked up all the freeview channels. I then proceeded with installing a labgear 4-way amp and supplied the aforementioned rooms with aerial points. When i plugged my test tv in it was fine, had all the channels as before. Then after watching tv for a bit it kept dropping out of signal and losing the picture. Hugely frustrating. The main culprits, channel-wise, are all the BBC channels and the itv channels! Looking at the neighbours they all have upgraded aerials, which was something i was trying to avoid!
Am i missing something or have i got to bite the bullet??

Many thanks in anticipation

 

[ericmark]

Freeview is split into around 6 multiplexed frequencies pre switch over these were dotted up and down the band where ever room could be found. Post switch over they are in most areas grouped.

This means pre switch over a wide band aerial is required but post switch over we can return to the smaller lighter narrow band aerials.

There are odd areas where even after switch over it needs a wide band (Often incorrectly called digital aerials) and some where the band has changed. At the end of your aerial there should be a bung which is coloured to show what band the aerial is designed for. You need to find out what colour is used in your area and check you have correct one.

The other problem not cured by aerial change is Sky boxes, VCR's and other devices using RF to send a analogue signal to TV's around the house. If one of these devices (Even in neighbours house) is set to same frequency as one of the multiplex signals then you can lose programs using that multiplex. In my area North Wales we had a problem with Channel 5 because Sky default in channel 68 and the multiplex that Channel 5 used was also on channel 68.

Easy way is to put TV to analogue and re-tune and see what it picks up and where. Note channel numbers 21 - 68 and see if same channel is used by a freeview multiplex signal. It took me quite a time to select free channels on my boxes as there is also interference caused on channels not selected due to harmonics.