Freeview in Mullingar

watty wrote: »

not really.

The most important things in decending order is
1) Height
2) Good Aerial array
3) very low loss good sheild down lead (Perhaps Satellite Cable)
4) Low noise Masthead amp. Small noise figure more important than gain. The gain is just mostly to compensate for downlead loss (18db perhaps). Too much gain simply amplifies noise and co-channel interference.

The gain of the masthead amp easily compensates any variation in sensitivity.

To reduce noise pickup effect in the cable I have approx 6 to 12dB too much gain in masthead amp and then an attenuator at the bottom of cable / tuner end. This reduces any noise injected by the power supply as it is after the PSU for the mast head amp.

I am thinking this may be the answer to problems I have been experiencing with Freeview HD reception over the months in S.Down.
I know the subject of variable gain in mast head amps has been discussed at length,but has come to the fore with receiving HD on T2,and its problems in rural areas.
Today,always allowing for high pressure lift trop etc,I find that by reducing gain on the MHA,HD signal strength is in the nineties,Quality in the 50's.Get the gain setting wrong,and sig.quality will disappear,along with HD Wales on Ch47.
Freeview SD,(As I call it) is 100% and rock steady.Aerial is cheap old Group B /V.
Now I know not to get excited,for as soon as the cup gets to the lip ,all will vanish,but will now use the same variable gain technique to IOM HD and SD transmissions which are much worse than I have seen before,hope the work at TX in May improves things?

Peter Rhea wrote: »

Take a look at this thread dealing with SFNs.

If you are receiving signals from more than one transmitter & depending on your exact location & the relative timing of these txs, you may be receiving 'echoes' that fall outside the guard interval, causing interference (though seemingly more so on T2).

These UK SFNs seem to be designed to serve small areas & rely on the seperate txs not intruding in each others' area too much (using different timing, polarisation, screening by terrain etc.) as the GI in use on UK transmissions is too short for 'proper' large area networks.

Lots of fun ahead,and as I have found,folk should not expect to pick up Freeview HD T2 just like that,especially if they assume their freeview is fine ,and upgrade to a new TV/STB.To quote the post,"DVB-T2 is worse as it uses fewer pilots than DVB-T" Thanks for that,pity I am outside the "Magic Zone " of 8.4KM.

Two things: If you actually read the charter, there's no rule against reviving old threads from death per se once the new post is relevant and an addition to the old discussion. E.g. an update on an old problem someone was having with their aerial etc would appear okay to me. The only specific rule in this regard is that posts must be on-topic and relevant.

Secondly, if there is something wrong with a thread isn't it up to a mod to decide and that's what the "report post" button is for?

Sponge Bob wrote: »

The specific explanation is given thus ( thread linked above from Digitalspy) and by our own RESLFJ, a broadly similar timings issue would arise were 3Rock and Kippure on an SFN as originally planned and were someone to try to tune into them in Wales.

http://forums.digitalspy.co.uk/showpost.php?p=49731759&postcount=7

Thanks for that,and Peter.
Are we saying that Wales can in effect stop me receiving the IOM channels(No Sig/Noise,Quality)?Interesting.
Can I dismiss the RTE (T) transmissions from the equation?
Does this mean the mods to the IOM Tx,due in May,can resolve this problem?
Perhaps we should move this back to "Thread re Co.Down",to avoid the sensitive issue of upsetting people which was never my intention.I simply picked up Watty's suggestion,and thought it very relevent to the subject today.

Peter Rhea wrote: »

The reference to Wales was only to explain the SFN effect from another viewpoint.

What we have been discussing here is the possible reception of at least two IOM signals at your location which may be causing destructive interference due to falling outside the cofdm symbol guard interval (GI).

Without knowing the relevant path lengths (I suspect they differ by slightly more than 8.4km in the Annalong area) & timing of each tx, we can't be sure what the situation is.

Of course this doesn't rule out CCI from another tx such as Llanddona.



Think that's a case of wait & see (unless you know what they have planned).

Sorry,I now see what you are saying,and in all of this I guess the TMT or whoever are delivering a service to the IOM,and not Annalong,although the Postcode checker does suggest I will get a signal from there.

Peter Rhea wrote: »

Looking at a map of IOM with the Port St. Mary & Beary Peark txs it certainly seems that anyone within the service area will have less than 8.4km difference in path length to either tx.
Afaics, any exceptions are either blocked by the terrain or are in the sea (!), while further north other sites provide coverage.

The plot thickens!(With the weather?)
Massive sig coming in on ch 58 (QVC 5USA ESPN CITV TV X Mux)
Massive sig coming in on ch 61 (e4+1 Sky news pick tv Mux)
All IOM and RTE pictures gone.On a search TV can't find them on ch43 47 and 50HD IOM and 54 RTE,although they are there at 100% sig strength,no quality,no picture!
Did someone tweek their sig up recently or will what passes for normality return with the rain on Thursday?