UPC Digital Channel Frequencies?

bk

Does anyone know what frequencies UPC use for their Digital Channels?

Not looking for this information for any dodgy reasons, I know you can't "tune in" DVB-C channels on your TV. The reason I'm interested in this, is to see what the current configuration of UPC's current network is and how this might effect it increasing Broadband service speeds in future might be.

We obviously know with the Analogue TV channel frequencies are and it is easy to discern the frequencies broadband use from your own UPC modem. That just leaves the DVB-C channels frequencies to be a mystery.

The Cush

bk wrote: »

I know you can't "tune in" DVB-C channels on your TV.

Some TVs have a DVB-C tuner and a number of the channels are unencrypted, maybe someone would be able to check.

L1011

I'll see if I can do a mux scan on my LG TV with a -c tuner. They're getting more common due to standardisation as a number of countries don't encrypt the basic channels

bk

That would be great, thanks

BTW that is really interesting, what digital channels are unencrypted? Are they the same as the 17 analogue channels?

dam099

bk wrote: »

That would be great, thanks

BTW that is really interesting, what digital channels are unencrypted? Are they the same as the 17 analogue channels?

I think it may be just RTE1, I accidentally used the DVB-C option when tuning a few weeks ago and it tuned in a load of encrypted channels but only RTE1 was clear.

The Cush

This is a list from July last year - http://www.boards.ie/vbulletin/showthread.php?p=91110196

watty

They can use any channel between 110MHz and 862MHz, or even higher*. Any downstream channel can be analogue, digital TV or DOCSIS.

Some cable systems don't reserve 87.5 to 108 for Radio.

Usually 5MHz to 65MHz (or a band within it) is the upstream channels for Broadband and is very rare now for Band 1 (42MHz to 68MHz approx) to be analogue TV.

[*Cable used to use only up to 560MHz, but can in theory on latest fibre fed cabinets with shorter coax use over 1000MHz as upper limit. Modern systems allow dynamic reprogramming of channel use and even switched video channels in the cabinet]

Antenna

It would be interesting if a subscriber with a DVB-C capable TV would make a list of the various MUX frequencies for digital cable for their area, provided that the TV could tune in all the encrypted channels and show the frequency (which is the centre frequency of an 8MHz TV channel MUX )

I'd be curious to see if any DVB-C cable MUX overlaps with for example amateur radio bands
particularly
70cms (430 - 440MHz)
and 2 metres (144-146MHz)

or are these frequencies left unused by the cable operators (I suspect they are)?

Likewise what DVB-C channels could be upset by PMR 446MHz walkie-Talkies if there was signal ingress and one of the cable MUXs goes across 446MHz?.

There have been postings here in the past about RTE DAB in Dublin degrading/putting noise on BBC2 analogue on Dublin cable, there is no reason why digital DVB-C could not also be affected (causing freezing etc) by other transmissions depending on signal strength and the screening quality of cable, particularly cables and sockets at the subscriber end.

watty

or are these frequencies left unused by the cable operators (I suspect they are)?

No they are not.
The TV won't show channels used for DOCSIS (usually 8MHz in Europe and 6MHz in North America). DOCSIS downstream data is essentially DVB-C modulation and the user data multiplexed using MPEG2-TS. Upstream is CDMA or TDMA (usually TDMA virtual channels) using any desired mix of 0.8MHz, 1.6MHz, 3.2MHz or 6.4MHz channels.
A modem powered up first tries last used downstream channel, if that fails, then looks at EVERY channel for DOCSIS info in the MPEG2-TS. It then sees the return channel and timeslot to request channels. Then it gets actual downstream and upstream to use, if a valid Modem that's registered, or else it's ignored.

A spectrum analyser would show channels in use. A TV will only show some in use channels. Perhaps I'll have a look in Limerick. But my HP141T is very heavy. I don't have 1.2GHz plug in, only 110MHz and 18GHz units. But the 18GHz one will cover 10MHz to 1200MHz

http://www.azur-electronics.com/Pages/hp_8555a_spectrum_analyzer_rf_section.aspx


It's cable, it's not supposed to leak in or out. Though some areas of bad cable the DAB was leaking in and causing trouble.

The Users Transmission in same room of 4G Modem or phone on 800MHz will disrupt Modem or TV easily
Double screened cable and decent F-Connectors helps.

Antenna

watty wrote: »

No they are not.

Watty, actually they are if what is here is still valid (dates from 2002)
(Technical Conditions for the Operation of Digital Cable Television Systems)

http://www.comreg.ie/_fileupload/publications/ComReg9866R.pdf

144 – 146 MHz (amateur 2 metre band) and 430 – 440 MHz (70cms band) Use prohibited (along with aircraft and marine/air distress frequencies)

I assume due to representations from the IRTS
two concerns:
(1) Amateurs not wanting TVI complaints from nearby cable viewers about their 2m/70cms transmissions possibly affecting certain channels on nearby cable TV (even though the fault is not with their own equipment)
(2) even small amounts of leakage interference would be noticed in amateur bands (analogue TV causing vision buzzing sounds or FM TV audio, digital TV causing increased noise)

watty

So no wonder Virgin media complained about TV spectrum sell off.
(which hardly benefits Mobile users at all, just saves Mobile operators some money, and cash influx for all the governments for licence. Theft from TV viewers, esp. the 700MHz band now proposed)

Anyway, next time I'm feeling energetic I'll measure what there is. Take photos etc.

white_westie

On the channel front, after doing a DVB-C scan on my TV a few weeks ago, and going through all the 100+ channels, I found the following 'open'

RTE1
RTE1+1 (maybe News not sure now)
Euronews
S*y A*ts 2
B* Sp 2 (surpised at this)

STB.

bk wrote: »

Does anyone know what frequencies UPC use for their Digital Channels?

Not looking for this information for any dodgy reasons, I know you can't "tune in" DVB-C channels on your TV. The reason I'm interested in this, is to see what the current configuration of UPC's current network is and how this might effect it increasing Broadband service speeds in future might be.

UPC Dublin (all at 64QAM @ S/R 6887)

150000
166000
291000
299000
307000
315000
323500
339500
347500
356000
364000
372000
418250

watty

Must be an area with poor cabling. 64QAM is low for modern cable.

STB.

watty wrote: »

Must be an area with poor cabling. 64QAM is low for modern cable.

Yes that struck me as odd. I grabbed it off a DVB-C dump for Dublin posted on Mediaportal. Of course it could be "Digital" MMDS. That would make sense for the QAM rating.

The channel block variations for Digital UPC is below, just not the frequencies.

http://support.upc.ie/app/answers/detail/a_id/256/~/activation-code

bk

So the overall make up might look like so:

36 MHz - DOCSIS Upstream (64QAM)
44 MHz - DOCSIS Upstream (64QAM)
55.2MHz - DOCSIS Upstream (64QAM)
61.6MHz - DOCSIS Upstream (64QAM)
150 MHz - DVB-C
166 MHz - DVB-C
176 MHz - Analogue TV
184 MHz - Analogue TV
192 MHz - Analogue TV
200 MHz - Analogue TV
208 MHz - Analogue TV
216 MHz - Analogue TV
224 MHz - Analogue TV
232 MHz - Analogue TV
248 MHz - Analogue TV
256 MHz - Analogue TV
264 MHz - Analogue TV
272 MHz - Analogue TV
280 MHz - Analogue TV
291 MHz - DVB-C
299 MHz - DVB-C
307 MHz - DVB-C
315 MHz - DVB-C
323.5 MHz - DVB-C
339.5 MHz - DVB-C
347.5 MHz - DVB-C
356 MHz - DVB-C
364 MHz - DVB-C
372 MHz - DVB-C
408 MHz - Analogue TV (Sky Living)
418.25 MHz - DVB-C
471 MHz - Analogue TV (E4)
482 MHz - DOCSIS Downstream (256QAM)
490 MHz - DOCSIS Downstream (256QAM)
498 MHz - DOCSIS Downstream (256QAM)
506 MHz - DOCSIS Downstream (256QAM)
543 MHz - Analogue TV
575 MHz - Analogue TV
682 MHz - DOCSIS Downstream (256QAM)
690 MHz - DOCSIS Downstream (256QAM)
698 MHz - DOCSIS Downstream (256QAM)
706 MHz - DOCSIS Downstream (256QAM)

Obviously just a rough idea out of interest.

The 400Mhz's look like bit of a mess, with Sky Living, E4 and that DVB-C channel all mixed up with lots of unused space around them.

Looks like plenty of space between 575Mhz and 682Mhz for at least another 8 downstream DOCSIS 3 channels there. Perhaps even an additional 8 in the 400MHz range if they reorganize and clean that range up a bit.

They might be also able to stick another 4 upstream channels in there at the bottom.

From above it looks like the Dublin network is built towards a 750MHz plant. Over the last few years they have been rebuilding a lot of the cable network and I assume much of it is 860MHz or even 1GHz. But I assume they can't take advantage of that extra capacity until all the cable in the same area (headend) is at the same level.

I assume the story is the same for them using 64QAM for DVB-C, I'm sure much of the network is quite capable of higher QAM for DVB-C, as we can see from the DOCSIS channels, but there are probably still old parts of the network that need to be upgraded before the headend can be switched to doing higher QAM levels.

All very interesting. Thanks for the info.

s_gr

Anyone have the frequencies for the UPC Galway cable system

icdg

We don't drag up old threads