MUX 2 launch date ?

lawhec

Booms wrote: »

Thanks, Watty.

I picked the Mux up by scanning that particular frequency into the box. (The autoscan only starts at IE or IF, it now identifies that frequency channel as ID, when I view the sig/quality strength in manual scan.)

So I'd assume that it is an actual transmission at 198.5 MHz, I wasn't looking at stored information from a stream, that I know of.

As an aside, the aerial used is a uhf grid, vertically polarised (which may be of no consequence, I'm not on a position to change it to horizontal to see the difference)

198.5MHz is the centre frequency for E8, which is allocated to Three Rock (10kW), Kippure (200kW) & Greystones (1kW) as a Single-Frequency-Network with vertical polarisation. This overlaps with with the traditional RTÉ Band III frequencies of IF & IG.

It could be the case that RTÉNL were firing up tests at Three Rock using a temporary Band III transmitting aerial, but it makes little sense to do so with the idea of deploying VHF transmissions when UHF isn't close to being squeezed. Can only think that either it was a short trial test that they carried out for training/potential future use, or that there was a private reason for such a test.

watty

Bizarre

Booms

Thanks for that Lawhec, very interesting information.

I was curious because no one else had mentioned seeing it. The Saorview boxes include VHF channels in their scan, and I thought other people would have noticed it. The signal is a bit intermittent at the moment, although still there, and if it is coming from Three Rock the receiving aerial is pointing directly away from it.

The horizontal aerial pointing to Three Rock isn't seeing it, (it does pause for quite a few seconds on "ch8" though) although Mux 1 is coming in fine. So maybe for digital signals aerial orientation is more effective at isolating the opposite polarisation?

As I've said before, where I am, I don't see any signal from Kippure, either ch54 or 58. Although my cousin's house 400 yards away, and at a lower elevation picks up Kippure's Mux 2 on his aerial which is aligned on Three Rock.

The scan says there are two "hidden services" - I presume that's standard with all the Mux 2 transmissions? And as I mentioned earlier, TG4 is on "test service 2" with a stated resolution of 1440x1088. Presumably that's also on other Mux 2 transmissions?

If they did use VHF frequencies, would they give increased coverage area compared to UHF? Could they be DX'd from further away?

The Cush

mickeyboymel wrote: »

Got something via email in work today from the retail support guys in Saorview, regarding a complete retune of all equipment being required on October 24th. Did not see it myself but will have a look in the morning....could this mean MUX2 is actually going to be fired up on this day too?

http://createsend.com/t/r-966963D1B43E60A7

The Cush

Booms wrote: »

Can't pick up Mux 2 form Kippure here, and there's none from Three Rock at the moment. But I'm receiving a Mux2 signal on VHF - frequency 198500, or Ch8 or ch ID.

The 198500 frequency has been mentioned by boards users previously

http://www.boards.ie/vbulletin/showthread.php?p=69473713#post69473713
http://www.boards.ie/vbulletin/showthread.php?p=70834550
http://www.boards.ie/vbulletin/showthread.php?p=79663013

Booms wrote: »

If they did use VHF frequencies, would they give increased coverage area compared to UHF?

This from a Saorview reply to a comment posted on on Facebook regarding the lack of Saorview coverage into a part of Wicklow currently receiving analogue VHF coverage but where UHF Saorview coverage won't reach

Michael Dunne
when will you lot have this place covered with Saorview ? Stranakelly Tinahealy county wicklow
7 October at 22:25

...

Saorview Tech & Trade The VHF analogue signal from Kippure is possibly reaching into the area at present but the UHF SAORVIEW signal won't reach it unfortunately.

http://www.facebook.com/#!/permalink.php?story_fbid=174126172724287&id=329691340422770

Hotblack Desiato

When I press Info my TR112 says "Frequency 738000kHz" but "Centre Frequency 198500kHz". It's tuned to Kippure on 5354, on a wideband UHF aerial that barely picks up Kippure analogue VHF at all. It's clearly NOT receiving on 198500, has it ever been properly explained why that figure appears?

watty

As I said earlier, it's one of the figures in the MPEG multiplex stream, seen it here on UHF Woodcock Hill

Getting nothing on 198500 in Fairview, though I only have an indoor aerial in fairness. Is it a 7 MHz carrier?

Hotblack Desiato

It's not a carrier at all it seems just showing up in the data stream for some unknown reason.

ninja900

ninja900 wrote: »

It's not a carrier at all it seems just showing up in the data stream for some unknown reason.

Yeah, 198500 has been defined as the default frequency in the TS for a long time.

Booms

Right, I'm confussed now.

Am I not picking up a mux on 198500?

I can accept people saying that they've scanned in a mux (say 73800) and that for some reason the data says "centre frequency 198500". Does anyone know if there's a reason for this?

But surely a manual scan of 198500 doesn't go and look at all available frequencies to find a carrier of that value present in some other mux in a completely different band?

The only info I get displayed is channel no./frequency and basic sig strength/quality bars.

Has anyone else picked it up or is it just me?

Thanks for trying Karsini. I don't know what the carrier setting is - I assumed it was 8MHz. Have you tried a scan with your aerial vertical?

watty

But surely a manual scan of 198500 doesn't go and look at all available frequencies to find a carrier of that value present in some other mux in a completely different band?

It might keep searching... I can enter ANY frequency on my Cable Modem (which is actually using a Microwave link) and it usually stops on 485MHz.

You might have a daft GUI on your receiver that reports the TS encapsulated data and not what the tuner actually tuned to.

Or the 198.5MHz exists in the TS table because RTENL are secretly using it near you.

Gerry Wicklow

I found the same mux several months back and still have it listed as 198500 with test cards and TG4 HD on channel 2. From the signal strength I'm guessing it is Kippure rather than 3Rock. This is using an older Ariva 200 combo. Up to now I thought I was imagining it

I'd say it probably is transmitting on VHF - I just can't get it here. The main mux shows 198500 as the base frequency but I'm getting no mux 2 at all, even on UHF.

Hotblack Desiato

Can anyone give me the dimensions for a coathanger Band III aerial to test this? I have a direct line of sight to Kippure from the attic window, but only a UHF aerial.

If they are testing VHF DTT, what is the point? All of the information has been that you need a UHF aerial for Saorview, no VHF transmitters have been announced. Would low power VHF be viable for areas like parts of Cork/Kerry with severe reception difficulties? But, given that Saorsat exists, what would the point be?

Johnboy1951

I knew I had seen that frequency someplace previously ......

[user@XPS ~]$ scandvb /usr/share/dvb/dvb-t/ie-Maghera
scanning /usr/share/dvb/dvb-t/ie-Maghera
using '/dev/dvb/adapter0/frontend0' and '/dev/dvb/adapter0/demux0'
initial transponder 690000000 0 2 9 1 1 3 0
>>> tune to: 690000000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_AUTO:QAM_16:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_4:HIERARCHY_NONE
0x0000 0x044d: pmt_pid 0x0000 RTÉNL -- RTÉ One (running)
0x0000 0x044e: pmt_pid 0x0000 RTÉNL -- RTÉ Two (running)
0x0000 0x044f: pmt_pid 0x0000 RTÉNL -- TV3 (running)
0x0000 0x0450: pmt_pid 0x0000 RTÉNL -- TG4 (running)
0x0000 0x0451: pmt_pid 0x0000 RTÉNL -- RTÉ News Now (running)
0x0000 0x0452: pmt_pid 0x0000 RTÉNL -- 3e (running)
0x0000 0x0453: pmt_pid 0x0000 RTÉNL -- RTÉjr (running)
0x0000 0x0454: pmt_pid 0x0000 RTÉNL -- RTÉ One +1 (running)
0x0000 0x04ca: pmt_pid 0x0000 RTÉNL -- RTÉ Radio 1 (running)
0x0000 0x04cb: pmt_pid 0x0000 RTÉNL -- RTÉ 2FM (running)
0x0000 0x04cc: pmt_pid 0x0000 RTÉNL -- RTÉ Lyric FM (running)
0x0000 0x04cd: pmt_pid 0x0000 RTÉNL -- RTÉ Raidió na Gaeltachta (running)
0x0000 0x04ce: pmt_pid 0x0000 RTÉNL -- RTÉ Radio 1 Extra (running)
0x0000 0x04cf: pmt_pid 0x0000 RTÉNL -- RTÉ Pulse (running)
0x0000 0x04d0: pmt_pid 0x0000 RTÉNL -- RTÉ 2XM (running)
0x0000 0x04d1: pmt_pid 0x0000 RTÉNL -- RTÉ Choice (running)
0x0000 0x04d2: pmt_pid 0x0000 RTÉNL -- RTÉ Gold (running)
0x0000 0x04d3: pmt_pid 0x0000 RTÉNL -- RTÉ Chill / RTÉ Junior (running)
Network Name 'RTENL 1'
>>> tune to: 198500000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_32:HIERARCHY_NONE
WARNING: >>> tuning failed!!!
>>> tune to: 198500000:INVERSION_AUTO:BANDWIDTH_8_MHZ:FEC_2_3:FEC_2_3:QAM_64:TRANSMISSION_MODE_8K:GUARD_INTERVAL_1_32:HIERARCHY_NONE (tuning failed)
WARNING: >>> tuning failed!!!

Booms

Thanks for the explanation Watty, obviously it's not as simple as I thought.

Gerry Wicklow - if it's a legitimate transmission it may well be Kippure. Although I'm not receiving either of Kippure's DTT channels here (never have that I know of, certainly nothing sinceThree Rock went to channel 30), we originally used channel 7 from there in the Sixties. So the VHF signal got through okay.

Ninja900 - a half wavelength dipole would be about 80cms or 30 inches. so if you stripped a piece of coax to make a dipole with half the above measurements on each side it would probably be about right. But don't forget that I'm using a vertical wideband UHF grid aerial, pointed about 120 degrees away from Kippure, so I would have thought someone line of sight would certainly be getting it.

Finally the boxes I'm using have very similar software, appearance and operation virtually the same. One's an early Walker box, the other an Alba Saorview from Argos. Both show and report the same channels except one calls the frequency channel "ID", the other "channel 8".

Gerry Wicklow

Rough snapshot. I'm not sure what the screen res is but to my auld eyes the DOG looked sharper than the official channel.

Antenna

lawhec wrote: »

198.5MHz is the centre frequency for E8, which is allocated to Three Rock (10kW), Kippure (200kW) & Greystones (1kW) as a Single-Frequency-Network with vertical polarisation. This overlaps with with the traditional RTÉ Band III frequencies of IF & IG.
.

It also overlaps the 192MHz and 200MHz channels on analogue cable, in Dublin RTE1 and UTV if the info in this post hasn't changed for those:
http://www.boards.ie/vbulletin/showpost.php?p=52793702&postcount=6

The introduction of RTE DAB caused noise/grain to appear on the 224MHz channel (BBC2) in Dublin for some cable viewers (depending on quality of installation) . Anyone notice similar on RTE1 and UTV on analogue cable in Dublin?

Gerry Wicklow

Gerry Wicklow wrote: »

Rough snapshot. I'm not sure what the screen res is but to my auld eyes the DOG looked sharper than the official channel.

Yep, that's 100% a VHF signal, it's a 7MHz carrier rather than the 8MHz used on UHF. Digital VHF uses the PAL-B 7MHz channels rather than the PAL-I 8 MHz channels.

The Cush

The GE06 VHF Ch08 (195-202 MHz) allocation is IRL DTT EAST 8 for Kippure, Three Rock and Greystones.

watty

Are they going to prove that people that bought UK or other UHF only boxes/TVs are idiots? I can't think that's the motive because plenty of unapproved (with or without MHEG, UK or not) TVs and boxes do have at least band III VHF. Some do Band I also.

Again secrecy and lack of openess in RTENL and RTE. Probably most of the people involved in the VHF test have no idea why they are doing it.

Antenna

lawhec wrote: »

It could be the case that RTÉNL were firing up tests at Three Rock using a temporary Band III transmitting aerial

There is already going to be a (vertical polarised) Band III transmitting aerial there for DAB, if they were testing Band III DTT they would likely combine both transmissions into the same aerial.

SRB

I still have good VHF analogue reception from Kippure, but not even a flicker of a DTT signal on that frequency. Either it's quite low power or is coming from another site.

lawhec

Antenna wrote: »

There is already going to be a (vertical polarised) Band III transmitting aerial there for DAB, if they were testing Band III DTT they would likely combine both transmissions into the same aerial.

It may or may not be the case - there would be a few technical considerations like the aerial transmission pattern, bandwidth, combiner handling etc. That is assuming of course that the signal is coming from Three Rock in the first place.

Ninja900's post gives a slightly plausible reason for such tests. It could be the case that there are low-power tests from Kippure using a temporary vertical Band III aerial (again there is a DAB aerial already up there but it may or may not be involved) as opposed to the current analogue TV Band III aerial which is horizontally polarised - The Cush a while back posted that someone had made contact with RTÉ that they lived in Co. Wicklow where they could receive RTÉ1 and RTÉ2 via VHF OK, but could get nothing for Saorview and asked if it would ever launch on VHF (no plans were the replay at the time). It could be the case that in some spots where Saorview currently doesn't reach, some low-powered VHF transmissions at specific sites that cover difficult terrain could deliver efficient coverage which UHF can't reach.

There are advantages and disadvantages in using VHF over UHF. The main disadvantage is the channel bandwidths being only 7MHz as opposed to 8MHz - the current Saorview mux delivers a bitrate of 24.128Mbit/s, the same configuration in 7MHz is 21.112Mbit/s or just slightly over a 3MBit/s loss. Increasing the FEC on a 7MHz mux to 3/4 from 2/3 gives a bitrate of 23.751Mbit/s which nearly makes it up at the expense of requiring a slightly stronger signal. Another disadvantage on VHF Band III is that man-made noise on this band is approx. 2db higher than on UHF. However, a lower field strength compared to UHF is needed, for example in Australia, in the main cities (Sydney, Melbourne, Brisbane etc) most DVB-T multiplexes are in VHF Band III while SBS is in UHF - the VHF muxs are 50kW while SBS is 200kW albeit remembering that Australia use 7MHz channels at UHF also. All of this is just a thinking-out-loud idea, but focusing on the Wicklow mountains for a test might be a good as terrain as any to try.

formerly scottish paddy

RTENL could be exploring some possible solutions for the situation in Kerry?
But how much receiving equipment is readily available for VHF DTT?

Sam Russell

formerly scottish paddy wrote: »

RTENL could be exploring some possible solutions for the situation in Kerry?
But how much receiving equipment is readily available for VHF DTT?

All Sarview approved equipment for a start.

Surely H polarization has a better reach than V. But it might be a good solution for the west coast to use VHF.

Another benefit of using 3Rock is the lesser travelling expenses.:)

radman

Ran a sweep on the carrier and came up with the following.
Carrier RTENL2
CH C08 198.5Mhz
64 Qam.
BW 7 Mhz
Guard 1/32
Carrier 8K
Code rate 3/4
Hierarchy none
There are 7 vision MPEG4 AVC video associated audio MPEG1 L2 at 192Kbit,
A number of audio only running at 128Kbit.
3 data channels? called.
Seirbhis trialach
Future service
SSU

It apperas to be vertical polarised and being transmitted from the Mast in Donnybrook.

The Cush

radman wrote: »

Ran a sweep on the carrier and came up with the following.
Carrier RTENL2
CH C08 198.5Mhz
64 Qam.
BW 7 Mhz
Guard 1/32
Carrier 8K
Code rate 3/4
Hierarchy none
There are 7 vision MPEG4 AVC video associated audio MPEG1 L2 at 192Kbit,
A number of audio only running at 128Kbit.
3 data channels? called.
Seirbhis trialach
Future service
SSU

It apperas to be vertical polarised and being transmitted from the Mast in Donnybrook.

VHF DTT testing, best not take down those VHF aerials yet.

Interesting first post Radman

Booms

radman wrote: »

R

It apperas to be vertical polarised and being transmitted from the Mast in Donnybrook.

That's a relief!. Won't have to requisition the Radio Direction Finder Van, now.

Many Thanks!