Full Freeview on the Divis (Northern Ireland) transmitter
 | Google Streetview |  | Google map |  | Bing map |  | Google Earth |  | 54.607,-6.009 or 54°36'24"N 6°0'34"W |  | BT17 0NG |
The symbol shows the location of the Divis (Northern Ireland) transmitter which serves 440,000 homes. The bright green areas shown where the signal from this transmitter is strong, dark green areas are poorer signals. Those parts shown in yellow may have interference on the same frequency from other masts.
Are there any planned engineering works or unexpected transmitter faults on the Divis (Northern Ireland) mast?
Divis transmitter - Divis transmitter: Possible effect on TV reception week commencing 11/11/2024 Pixelation or flickering on some or all channels 
_______
Digital television services are broadcast on a multiplexes (or Mux) where many stations occupy a single broadcast frequency, as shown below.
64QAM 8K 3/4 27.1Mb/s DVB-T MPEG2
DTG-12 QSPK 8K 3/4 8.0Mb/s DVB-T MPEG2
H/V: aerial position (horizontal or vertical)
Which Freeview channels does the Divis transmitter broadcast?
If you have any kind of Freeview fault, follow this Freeview reset procedure first.Digital television services are broadcast on a multiplexes (or Mux) where many stations occupy a single broadcast frequency, as shown below.
64QAM 8K 3/4 27.1Mb/s DVB-T MPEG2
DTG-12 QSPK 8K 3/4 8.0Mb/s DVB-T MPEG2
H/V: aerial position (horizontal or vertical)
Which BBC and ITV regional news can I watch from the Divis transmitter?
BBC Newsline 0.6m homes 2.5%
from Belfast BT2 8HQ, 1,044km northeast (51°)
to BBC Northern Ireland region - 46 masts.
Are there any self-help relays?
| Chapel Fields | Transposer | Central Belfast | 61 homes |
How will the Divis (Northern Ireland) transmission frequencies change over time?
| 1950s-80s | 1984-97 | 1997-98 | 1998-2012 | 2012-13 | 4 Mar 2020 | ||||
| VHF | A K T | A K T | A K T | K T | W T | ||||
| C1 | BBCtvwaves | ||||||||
| C21 | C4waves | C4waves | C4waves | +D3+4 | D3+4 | ||||
| C23 | SDN | SDN | |||||||
| C24 | ITVwaves | ITVwaves | ITVwaves | BBCB | BBCB | ||||
| C26 | ArqA | ArqA | |||||||
| C27 | BBC2waves | BBC2waves | BBC2waves | BBCA | BBCA | ||||
| C29 | ArqB | ||||||||
| C30 | LBT | ||||||||
| C31 | BBC1waves | BBC1waves | BBC1waves | ||||||
| C33 | com7 | ||||||||
| C34 | com8 | ||||||||
| C36 | _local | ||||||||
| C48 | NIMM | NIMM | |||||||
| C55tv_off | com7tv_off | ||||||||
| C56tv_off | COM8tv_off |
tv_off Being removed from Freeview (for 5G use) after November 2020 / June 2022 - more
Table shows multiplexes names see this article;
green background for transmission frequencies
Notes: + and - denote 166kHz offset; aerial group are shown as A B C/D E K W T
waves denotes analogue; digital switchover was 10 Oct 12 and 24 Oct 12.
How do the old analogue and currrent digital signal levels compare?
| Analogue 1-4 | 500kW | |
| BBCA, D3+4, BBCB | (-7dB) 100kW | |
| SDN, ARQA, ARQB | (-10dB) 50kW | |
| com8 | (-16dB) 12.7kW | |
| com7 | (-16.1dB) 12.4kW | |
| LBT | (-20dB) 5kW | |
| Mux 1*, Mux 2*, Mux A*, Mux B* | (-23.4dB) 2.3kW | |
| Mux C* | (-24dB) 2kW | |
| Mux D* | (-24.9dB) 1.6kW | |
| NIMM | (-47dB) 10W |
Which companies have run the Channel 3 services in the Divis transmitter area
|
|
Friday, 11 October 2019
MikeP
11:07 PM
11:07 PM
nobody:
But a poor connection introduced frequency selective impedances that are unwanted.
| link to this comment |
Saturday, 12 October 2019
nobody: Very good point!. The capacitive reactance (a few pF??) reactance may well be quite low at UHF, but I use flyleads for VHF and HF as well. Even unsoldered you'd probably get a good electrical connection,
but I think it is good practice, but I guess such ideas are also old-fashioned!
| link to this comment |
Denis's: mapD's Freeview map terrainD's terrain plot wavesD's frequency data D's Freeview Detailed Coverage
MikeP
12:02 PM
12:02 PM
Denis:
I agree. I used to have to deal with television reception problems and many of them stemmed from poor flyleads. Some were not soldered nor screwed together and they were the most common causes of problems. Those that were soldered gave the least trouble unless the inner core wire(s) broke. A few were screwed together and they only gave problems if they we moved whilst under tension.
Personally, I prefer to solder the wires in, much more reliable from my lengthy experience.
| link to this comment |
C
Chris.SE5:18 PM
nobody: & Denis:
I can vouch for the fact that MikeP is correct about frequency dependant impedances (and hence attenuation) from poor/broken connections in coax and flyleads based on my experience ;) Unless you've seen some of the "weird" effects it can have, you might not believe it!
| link to this comment |
Sunday, 20 October 2019
Divis Muxes.
LBT (NvTv) is listed as being on mux channel 30. I think this is a typo because Com6 is also listed as Mux 30.
LBT (TV chan 7) is actually on mux channel 36, which also hosts Sony (48), Sony Movies (50 and 60), and TinyTots (207), some of which are not listed.
Who can update these?
| link to this comment |
Denis's: mapD's Freeview map terrainD's terrain plot wavesD's frequency data D's Freeview Detailed Coverage
C
Chris.SE6:32 PM
Denis:
Only the site owner Briantist, and see seems rather busy to keep up with changes and errors. You are best referring to DigitalUK and Freeview websites for UK stuff.
| link to this comment |
Monday, 21 October 2019
Thanks Chris.
Pity, as this site has such a lot of information - which I can't find elsewhere.
Freeview and DigitalUK have little information apart from a channel listing. Their Clearance Checker shows no changes until next year, I guess that's because the previous change date 4th Sept 2019 has passed.
| link to this comment |
Denis's: mapD's Freeview map terrainD's terrain plot wavesD's frequency data D's Freeview Detailed Coverage
Tuesday, 22 October 2019
C
CP1:19 PM
Denis:
I'm about 4 miles from the Divis transmitter. I have an old loft mounted Labgear (I think) wideband 12-element Yagi. It's about 1.3m long. It might be overkill for my location, but it provides enough signal strength for me to passively split it four ways without problem. I've never actually tried a set-top aerial here.
The USB dongle I use for SDR is a NooElec NESDR Mini 2+. It has an R820T2 tuner and cost me about 20 from eBay if I recall. Software-wise I use SDR# on Windows, Spektrum as a spectrum analyser and Gnu Radio and rtl-sdr on Raspberry Pi / Linux, along with ADS-B and DVB-T2 decoders depending on what I'm doing.
| link to this comment |
Wednesday, 23 October 2019
Thanks CP,
Raspberry Pi is beyond me, though to I use Linux on an old PC.
I am plagued by electrical noise, perhaps partly due to LED lamps, hence my interest in a spectrum analyser. The noise affects VHF FM and some HF bands.
I presently have an 8-element log periodic in the roofspace feeding 6 flats through a distribution amplifier. Getting all the Divis channels, though the weaker muxes are a bit low, though useable (NvTv, Smithsonian and Freesports).
Other units in my development have two aerials, one vertically polarised, which I assume is for RTE Soarview from Claremont Carn. RTE is also transmitted from Black Mountain, but only four channels and with some programmes blocked due to broadcasting rights. Claremont Carn broadcasts 20 channels.
I'd be interested to hear from anyone getting Saorview, as to aerial and programme-guide issues.
| link to this comment |
Denis's: mapD's Freeview map terrainD's terrain plot wavesD's frequency data D's Freeview Detailed Coverage
C
Chris.SE2:57 PM
Denis:
I was wondering why you think part of your noise might be primarily due to LED lamps - rather than fluorescent - compact or otherwise?
Whilst the "classic" LED lamps have SMPS, they do generate less noise than compact fluorescents. However, "Filamentary" LEDs are pretty well noise free as they have no SMPS. The most common types are "clear" lamps, but there is an increasing number of "frosted" ones available from different suppliers. You also get better all round illumination from such lamps (similar to a standard A shape bulb) as they don't have a large plastic covered body at the rear of the lamp, just a normal size BC or ES cap.
It's just a shame that the prices of these haven't come down as much as the noisy classic ones.
| link to this comment |
Select more comments
Your comment please