Are Saorview ever going to add more channels?

Elvis Hammond

ka2 wrote: »

... I remembered seeing a chart for RTE which seemed to suggest that most RTE sites were vertical only. Three Rock and Kippure were mixed.

Yes, that's probably still the case; I think the same claim was made relatively recently by someone more knowledgeable than myself, although the document from Comreg about 5 years ago had most sites as mixed.

dxhound2005

Another legacy from the early days of VHF in the UK is the frequency usage. The band went between 88 and 100, and later 104 I think before the current 108. No BBC transmitters in England go above 100 for Radios 1 to 4, and not many elsewhere in the UK. And possibly the highest is 104.9 for any BBC service. Independent stations go higher.

Anyone buying a vintage transistor radio, could be restricted to 88 to 104. Nice things to own, but not much use for Newstalk.

Harry Palmr

Also something to remember if importing vintage Hi Fi gear from Japan (Fm ends at 95 MHZ) and why you need to adapt (or replace) the radio with a car imported from Japan.

ka2

dxhound2005 wrote: »

Another legacy from the early days of VHF in the UK is the frequency usage. The band went between 88 and 100, and later 104 I think before the current 108. No BBC transmitters in England go above 100 for Radios 1 to 4, and not many elsewhere in the UK. And possibly the highest is 104.9 for any BBC service. Independent stations go higher.

Anyone buying a vintage transistor radio, could be restricted to 88 to 104. Nice things to own, but not much use for Newstalk.

This is true. My family had a stereo system from the early 80s which only went up to 104.

I also heard a story before (not sure how true) that 98FM were originally allocated 105.5 but objected to the frequency on the basis that a large number of radios couldn’t receive it. So ODTR allocated them 98.1 on a temporary basis and tried to move them again for Lyric FM. They objected again because the frequency was an integral part of their branding. 105.5 is now used by Today FM from Clermont Carn instead.

L1011

There has been mass resistance to radio stations using their frequency as part of branding since then. Hasn't stopped it entirely, Nova launched as Nova100 and the two iRadios used frequencies in branding before merging as the most recent ones.

TAFKAlawhec

Throwing some €0.02 in here regarding FM radio...

The original VHF FM Radio band in Europe only extended from 87.6 - 99.9 MHz, and this was the case also in the Stockholm 1952 &1961 bandplans for the European broadcast area that was the basis for VHF & UHF radio & television. The Geneva 1984 bandplan cleared this up to 108MHz, though some countries had already expanded upwards from 100MHz before then (not sure of the dates).

The ST52 bandplan for VHF Band II didn't have any allocations for RoI IIRC, while the UK was still mulling over wherever to use AM or FM for sound broadcasting in the band (all other sound broadcasts in the band on the continent at that time were already FM) and had different allocations depending on what would eventually be adopted. Shortly after the conference, they settled on FM.

The ST61 bandplan for VHF Band II allocated for the Republic of Ireland essentially two national network sets of frequencies while the UK had settled on a three national network bandplan, which is still used on this basis today for 88 to 94.6 MHz.

I don't know about the RoI, but in the UK much of the band from 95 MHz up (to 108 MHz) was used by the Home Office and by the police and over the decades these were only cleared on a piecemeal basis. The last bit (105 to 108 MHz) was only finally cleared in the mid-90s. It was also a reason why up until the early 90's prisoners in the UK were not allowed radios that could receive FM, lest they were able to tune in to "the filth".

Sometime around the early to mid-80's (not exactly sure of the date, could have been before or after the GE84 conference) the Irish authorities struck an agreement with their British counterparts to allow for the RoI to have three national FM networks based on the UK plan of three main stations separated nominally by 2.2 MHz each. This allowed RTE Radio 1 & RnaG at the time to have their own separate FM networks than sharing one together. In some cases, this also allowed for power increases on both sides of the border.

The original UK VHF FM radio transmissions were all horizontally polarised. The is because at the time of launch, car radios were a luxury item (and if they did, few had FM) and most such listening was for home consumption, intended for use with a roof-top two or three element aerial to a dedicated receiver, either a standalone receiver usually part of a Hi-Fi system, or combined with a television. The BBC technicians in their tests found that horizontal polarisation suffered less from polarisation twist for over-the-horizon reception, and that multipath interference was also less compared to vertical polarisation (not taking into account the more "directional" properties of a horizontal dipole anyway). Most such high-powered VHF FM transmitters in continental Europe were also horizontal polarised only as well, some still are today - the prevalence generally depends on policy by country.

The start of the shift in the UK for the BBC national FM radio network to move towards mixed polarisation was from the original policy of the IBA to have all their ILR stations transmit with circular polarisation. As the VHF FM Band was starting to be included in more transistor and car radios, this provided improved reception capabilities, especially for car radios - transistor radios at least were static and could have their telescopic aerials angled, something that car radios couldn't adjust to. The Beeb's engineers took note of this approach and with many of their original high-powered VHF FM transmitter stations coming up to needing refurbishment as well the the 405 line TV network due to be closed within a few years, they set out to re-engineer the VHF FM network not only for mixed polarisation but also to ensure new TX aerials could also handle future transmissions in the rest of an expanded Band II (e.g. BBC Radio 1). The first main BBC station converted for mixed polarisation was Wrotham in 1981 - IIRC, Divis was one of the last to be converted to mixed polarity by around 1990 - both Brougher Mtn. & Derry were converted several years prior.

RTE's original Raidio Eireann FM network was launched in 1966. I'm not entirely sure why most of the sites were vertical polarisation only, contrary to their UK counterparts (it may have been to do with portable reception, but I don't know either way). From memory, the five 2RN "national" FM networks of Radio 1, 2FM, RnaG, Lyric FM & (a slightly modified) Today FM only have mixed polarisation transmissions at Three Rock, Kippure & Holywell Hill, with all other transmissions vertical polarity only. An old pamphlet from the 1980's for receiving RTE on VHF FM had indicated that Clermont Carn was to use circular polarisation, but later publications had changed this to only vertical.

dowtchaboy

TAFKAlawhec wrote: »

I'm not entirely sure why most of the sites were vertical polarisation only, contrary to their UK counterparts (it may have been to do with portable reception, but I don't know either way).

My 2c worth - I was told by a contact at RTE in 1976/77ish that the reason for mainly vertical polarisation on the VHF TV and FM transmitters was that this gave better penetration in hilly areas. Maybe this would also they would require less fill-in transmitters? I think, but am not sure, that when they later started to put up fill-in transmitters these were mainly horizontal to take advantage of less interference with the same frequencies broadcast by vertical polarised transmitters?
To be honest, the discussion I would have been having back then would have been related to TV rather than FM.
It was a long time ago and it's all rather analogue and fuzzy in my head!