RTÉ DTT Tests: Mullaghanish

dunleas

Antenna wrote: »

All 6 national FM radios are currently off from Mullaghanish since some time this morning, I presume due to the replacement mast work.



UPDATE: noted back on 12:30

hmmmm Radio1 and 2fm still down here.....

Voyager II

All back now:)

Antenna

dunleas wrote: »

hmmmm Radio1 and 2fm still down here.....

they all came back temporarily (for lunchtime?), then went off again (and still off)

TV unaffected AFAIK

Voyager II

Antenna wrote: »

they all came back temporarily (for lunchtime?), then went off again (and still off)

As of 16:27 all radio and tv channels working here old head of kinsale from mullaghanish.

pa990

two audio streams now on RTE1, RTE2, TG4.

second audio is silent at the moment

kinsaleferg

Am about 3 miles south of Innishannon.

Red Band A aerial for Mullaghanish hung off of fishing gut in the attic. No Amp.

Philips 32PFL5404H (setup to do UK scan so I can see the MHEG apps) shows 16 channels. 40% strength 'Good' Quality

Have had standard RTE channels + radio + News Now for several months

Most recent addition is the suite of RTE DAB channels which are being rebroadcast on DTT.

Might get a cheap DTT STB(with audio out) to be my DAB receiver while we wait for DAB proper

TheDriver

I can't get any audio on RTE1 but tv shows 3 audio feeds but all silent.
Lot of radio stations appearing now too

kinsaleferg

RTE 1 - I think it may be the audio description stream, might show as NAR. Its not broadcasting on the show I am watching right now, but theres a holder for it.
The main audio is fine but I am fairly sure this is a mono recording (buddy holly show)

Stinicker

Anyone here getting the MHEG5 Digital Aertel Teletext from Mullaghanish? I was receiving it previously but am not not now!

The Cush

Stinicker wrote: »

Anyone here getting the MHEG5 Digital Aertel Teletext from Mullaghanish? I was receiving it previously but am not not now!

Working here together with the MHEG-5 epg (green button).

Machinehead

The Cush wrote: »

The RTÉNL rollout schedule indicates that power output will be 40kW from the new mast and antennas up from 20kW with final power output of 200kW at ASO.

Crush. Does this mean that DTT is only operating at 20% of it's proposed power & that strength & quality are to improve futher? At the monent I have 100% signal strength with 30-40-50% quality with bit error rate all over the place & clear blue skies. I'm really confused in that I've just had a new hi-gain areial installed with the intention of getting signal from my usual VHF/UHF mast - Maghera (channel 48) - but I've got a stronger signal from Mulla (channel 21) with the aerial pointing 90 degrees from the Mulla mast getting the signal broadside rather than pointing directly at the mast. (i.e. almost exactly half way between both masts). Comments please.

The Cush

Machinehead wrote: »

Crush. Does this mean that DTT is only operating at 20% of it's proposed power & that strength & quality are to improve futher?

The final figure for Mullaghanish is 200kW at ASO. There's a new taller mast under construction there and according to More Music recently, new UHF antennas have been installed also some posters here have reported receiving DTT from Mullaghanish further from the transmitter possibily due to higher power tests from the new taller mast which would explain your improved reception.

I receive Woodcock Hill DTT side on my Mullaghanish aerial but cannot pick up analogue from Woodcock Hill even with the correct aerial pointing in the correct direction.

mossym

Machinehead wrote: »

Crush. Does this mean that DTT is only operating at 20% of it's proposed power & that strength & quality are to improve futher? At the monent I have 100% signal strength with 30-40-50% quality with bit error rate all over the place & clear blue skies. I'm really confused in that I've just had a new hi-gain areial installed with the intention of getting signal from my usual VHF/UHF mast - Maghera (channel 48) - but I've got a stronger signal from Mulla (channel 21) with the aerial pointing 90 degrees from the Mulla mast getting the signal broadside rather than pointing directly at the mast. (i.e. almost exactly half way between both masts). Comments please.

surprised you were getting maghera in the past and not mullaghanish, i'm up in clare/tipp(right on the border) and was expecting maghera but mullaghanish was all i could get, and i'm only 20km as crow flies from maghera

I am on the shannon though so we are down in the valley so that could explain it.

Machinehead

Yeah, it seems obvious that I should access Mullaghanish but I live live on the southwestern side of Tralee, at the base of & in the shadow of the Slieve Mish Mountains, never any Mulla VHF/UHF rond here! My neighbours & I all point to Maghera for what is a crap analogue signal. As mentioned in my post to Crush, I get best signal from Mulla with the aerial positioned at 90 degrees to the mast. Stength is at max but quality is only 40% & my concern is that in poor weather I will loose everything.

lucernarian

What's the signal from Maghera like on Ch 48? Like is quality better than Mulla? Signal strength is not so important per se.

Machinehead

To_be_confirmed wrote: »

What's the signal from Maghera like on Ch 48? Like is quality better than Mulla? Signal strength is not so important per se.

Now at 10%, but not pointing directly at Maghera. When pointed directly I was getting 30-40% quality but the bit error rete was far worse than what I have from Mulla (hence a lot of picture break up). Just wish RTÉNL would post power output & tests for their masts on their web site so ppl would know where they stand esp in marginal reception areas:(

Machinehead

Update: Mullaghanish signal quality now at 10%. Is there some tweeking going on there? - massive picture breakup. Maghrea 10% also.

Stinicker

Machinehead wrote: »

Update: Mullaghanish signal quality now at 10%. Is there some tweeking going on there? - massive picture breakup. Maghrea 10% also.

I am receiving the same strength from Mullaghanish as I always was! Quality is varying between 60 to 90% for me.

co channel or long distance reception of competing transmitters is rife today and could be the most likely cause of the dips in quality and occasional programme drop outs.

irishchris

has anyone any audio sync probs on rte1/2/news now.
my sound is out using a usb tuner on vu+. not sure if its a prob with dtt from maghera or if its the driver issue as vu+support for it is new

Machinehead

I know that my signal is marginal but quality still at 10% down from 40-50% 24 hours ago - must be engineering work or something. Couldn't be that my aerial has shifted since yesterday:(

TheDriver

maybe its the weather, other signals that usually don't count might be strong enough in the high pressure to get through and interfere

Machinehead

I thought DTT was ment to be impervious to atmospheric conditions that "murder" VHF, if that were the case, what happens in countries with warmer climates - surely they don't suffer broadcast interferance during their hot summers. Anyone know of a site where a mole from RTÉNL might be posting "work in progress" updates?;)

DTT is not impervious to co channel.

It's a case when theres co channel of you either have one or the other channel with some break up or no channel at all.

You would first notice it by observing signal quality when in fine weather like now.
Signal quality will vary a lot and be going up and down like a yo yo.
That reflects both signals rising and dropping in strength versus each other and the interfering one nearing the threshold of signal quality to out do the other signal.

The difference between digital and analogue pictures is with digital,you either have it or you don't.
So in co channel,you would always have wavy lines on analogue pictures but with digital,you wouldn't know about co channel untill it passes the other channels signal threshold or equals it.
Prior to it doing that,you have a perfect picture whereas with analogue you had a bad picture even with weak co channel interference.

When it equals it,you get nothing at all as if the tx is off air but if you do a signal test,you will see the signal is there but quality has gone below 20%

Hope that explains it in layman's terms.

dnme

I'm in south Co. Sligo, my DTT is gone, I notice that when I rescan, I am picking up a weak UK DTT signal, so maybe there is one cancelling the other out. Oh well back to analog for the evening.

Machinehead

Deleted User wrote: »

DTT is not impervious to co channel.

Understood. But a little clarificaton. Does co channel exist due to interferance from other DTT channels or just VHR/UHF or a combination of all? Will the ASO in 2012 solve the problem. Is the possibility of co channel greater if RTÉNL decide to reduce power on their test transmissions? Also in fairness atmospherics haven't changed that much in the past 24 hours to explain the reduction of 30% in signal quality. At the moment: quality 10% - strength 100%. BER 1.47/3.64-02. Last night quality 40-50% - strength 100%.
BER 3.5/5.5-05. What is the optimum BER? Thanks for the help!
In the meantime I've just to lay claim to sat box for the world cup as I don't have a deacent analogue option. Nice to have the DTT option while it lasted.

lucernarian

BER should be 0 ideally. But I think it's supposed to be anything below 1x10^ -7
So the numbers are very high, with according low quality.

In my experience, it's unusual to see a DTT box reaching 100% signal. It sounds like the amp being used could be too powerful. I think you should manage a better signal from either Maghera or Mulla, terrain and all, so I wouldn't rule DTT out yet.

Do you have any details on your setup at all? Like what Group aerial it is? (http://www.aerialsandtv.com/aerials.html#aerialgroups) You don't need to go through the whole article, basically the aerial will have a coloured tip which will tell you what group it is. Is the aerial outside or not?

It can be the case aswell that cables used are mediocre and don't have enough shielding. For someone getting 40% quality, having a shorter or better quality cable can make all the difference. That website has got tonnes of info on that if you want to find out more!

Machinehead

Machinehead wrote: »

Understood. But a little clarificaton. Does co channel exist due to interferance from other DTT channels or just VHR/UHF or a combination of all? Will the ASO in 2012 solve the problem. Is the possibility of co channel greater if RTÉNL decide to reduce power on their test transmissions? Also in fairness atmospherics haven't changed that much in the past 24 hours to explain the reduction of 30% in signal quality. At the moment: quality 10% - strength 100%. BER 1.47/3.64-02. Last night quality 40-50% - strength 100%.
BER 3.5/5.5-05. What is the optimum BER? Thanks for the help!
In the meantime I've just to lay claim to sat box for the world cup as I don't have a deacent analogue option. Nice to have the DTT option while it lasted.

The standards for decoding dtt signals are a different page altogether to analogue reception.

You can have fine weather and no co channel even with high pressure and you can have it in low pressure! but its very common in high pressure.
It's actually tropospheric ducting that causes the co channel with the far away signals damaging the local one and even over riding it.

Reducing power would enhance the problem.


Theres actually a forecast here for the tropo and as you can see it's going to be pretty exstensive over the coming days.

lucernarian

Out of interest, where could tropospheric ducting be coming from on Ch 21, especially in Tralee? Caradon Hill? Divis? It seems very extreme if it's from those sorts of distances. I've only seen that sort of effect once in 4 years of messing around with DTT.

To_be_confirmed

To_be_confirmed wrote: »

Out of interest, where could tropospheric ducting be coming from on Ch 21, especially in Tralee? Caradon Hill? Divis? It seems very extreme if it's from those sorts of distances. I've only seen that sort of effect once in 4 years of messing around with DTT.

Regular reception of caradon hill in normal conditions has been reported in Kinsale.
I could also get it in analogue here poorly with a group A in normal conditions and very good in fine weather.
So it's not *that* extreme at all.

What is extreme is Gerry Wicklow reporting here getting french dtt yesterday on a grid pointing to presely.

Proper Tropo is a dx'ers heaven if they have the right aerials.
We've got spanish fm here with rds during it and once even italian stuff.

The likes of caradon and Blaenplwyf [It's SW beam] are near enough to be more regular visitors or troublemakers depending on what you want.