UK offset-carrier (“climax”) frequencies:
119,525 ACC MANCHESTER ACC(TRENT) 119,725 ACC LONDON ACC(DIRECTOR NORTH) 120,025 ACC LONDON ACC(NERCSBY5A) 120,475 ACC LONDON ACC(TC South 270+TC South D)(*) 123,950 ACC SCOTTISH ACC(OCEANIC) 124,900 ACC NORTH SEA(WEST OF SHETLAND) 125,275 ACC NORTH SEA(ANGLIA RADAR) 125,950 ACC MANCHESTER ACC(STBY PT1) 125,950 ACC SCOTTISH ACC(PC WEST STNDBY) 125,950 ACC MANCHESTER/MANCHESTER(STBY PT1+STBY PT2) 126,875 ACC LONDON ACC(NERCSBY4) 126,925 ACC SCOTTISH ACC(MONTROSE COMBINED) 127,275 ACC SCOTTISH ACC(WESTCOASTB) 127,525 ACC LONDON ACC(Heathrow Standby 2+Heathrow Standby)(*) 127,650 ACC SCOTTISH ACC(OCEANIC) 127,700 ACC LONDON ACC(NERCSBY3) 128,675 ACC MANCHESTER ACC(SCOTTISH NORTH UPPER) 128,925 ACC NORTH SEA(ANGLIA RADAR 2) 129,100 ACC SCOTTISH ACC(RATHLIN) 129,225 ACC SCOTTISH ACC(MORAY HIGH) 131,050 ACC LONDON ACC(LONDON ACC AREA 1B+LONDON ACC AREA 1C+LONDON ACC AREA 1A+LONDON ACC AREA 3)(*) 131,300 ACC NORTH SEA(SUMBURGH RADAR) 132,300 ACC LONDON ACC(LONDON ACC AREA 4B+LONDON ACC AREA 1B+LONDON ACC AREA 1C+LONDON ACC 2A+LONDO 132,550 ACC NORTH SEA(REBROS NORTHB+REBROS SOUTH2) 133,450 ACC LONDON ACC(TC North E FL 120+TC NORTH E B)(*) 133,525 ACC LONDON ACC(U3+U4) 133,675 ACC SCOTTISH ACC(HEBRIDES) 133,800 ACC MANCHESTER ACC(SCOTTISH EAST P2+EAST+SCOTTISH EAST P3+SCOTTISH EAST P1)(*) 133,975 ACC LONDON ACC(TC NORTH STNDBY) 134,100 ACC SCOTTISH ACC(NORTHERN NORTH SEA) 134,425 ACC MANCHESTER ACC(STAFA) 134,850 ACC SCOTTISH ACC(MORAY LOW) 134,975 ACC LONDON ACC(DIRECTOR SOUTH) 135,175 ACC NORTH SEA(REBROS NORTHB+REBROS SOUTH2) 135,325 ACC LONDON ACC(LAMP 270b+NERC16(NEW)+NERC 18)(*) 136,575 ACC MANCHESTER ACC(SCOTTISH NORTH LOWER) 136,600 ACC LONDON ACC(NERC STANDBY2B) 118,950 APP 510900N 001100W 120,400 APP 512800N 002700W 120,625 APP 515300N 001400E 122,250 APP NORTH SEA(BRENTRADAR) 125,625 APP 512800N 002700W 126,825 APP 510900N 001100W 128,025 APP LONDON/CITY(Thames Radar) 128,750 APP 515300N 002200W 128,750 APP 555200N 042600W 129,025 APP 510900N 001100W 129,550 APP 515300N 002200W 131,300 APP 595300N 011800W 132,050 APP 515300N 001400E 132,700 APP LONDON/CITY(TC THAMES Radar) 136,200 APP 515900N 002100E 136,200 APP 515300N 001400E 119,875 FIS SCOTTISH ACC(FIR) 124,600 FIS LONDON ACC(FIS EAST) 124,750 FIS LONDON ACC(FSW FL110+FSW FL125+FSW FL200+FSW+FSW FL75)(*) 125,475 FIS LONDON ACC(FIRN) 125,725 VOLMET 563000N 040300W 126,600 VOLMET 512800N 002700W 128,600 VOLMET 512800N 002700E 135,375 VOLMET 512800N 002700E
Peter wrote:
Since there is no detectable difference between using 125.000 on a 25k radio and using 125.005 on an 8.33 radio, why not?I don’t really know, but I can make two guesses:
There has also been mention of keeping FIS frequencies in northern Sweden on 25 kHz channels for the same reason. I haven’t heard how that is progressing, but there is still half a year to go…
Sweden will keep twelve 25 kHz channels for club and school purposes for at least 10 years.
Since there is no detectable difference between using 125.000 on a 25k radio and using 125.005 on an 8.33 radio, why not?
sugarcube wrote:
So it appears even after the “complete” switch to 8.33, dozens (or even hundreds) of 25khz frequencies willl remain in use. Quite a different story then i heard before, some people told me that very soon after 01/2018 all 25khz will be converted to 8.33 khz, only 121.5 will remain.Even if you don’t count the offset carrier channels, there are other exceptions. E.g. Sweden will keep twelve 25 kHz channels for club and school purposes for at least 10 years.
Peter wrote:
This popped into my email yesterday. Offset carrier (“climax” – what an unfortunate name ) usage in Europe
Anyone knows what these numbers mean ? Are these the number frequencies using offset carrier, or are these the offsets/number of base stations (thus the number of actual frequencies multiplied by 2, 3, 4…)
So it appears even after the “complete” switch to 8.33, dozens (or even hundreds) of 25khz frequencies willl remain in use. Quite a different story then i heard before, some people told me that very soon after 01/2018 all 25khz will be converted to 8.33 khz, only 121.5 will remain.
What is funny about the above map is how the UK is the top country for using offset carriers – for stuff like London Info. These cannot go to 8.33 because their operation needs the “more sloppy” receivers.
@Peter – I will email you the PDF
That’s very weird. If I click on the link in my usual browser, I get the PDF. If I click on the link from another browser, I get a 404 error. Hmm.
As I know the Eurocontrol links to be unreliable, there is a manual option via the secondary route for which I provided instructions.
Unfortunately that Eurocontrol URL appears to have been dead for some years… I know they change the token monthly (presumably a crude attempt to prevent people creating links to the database) but even the PDF itself, while referenced variously on the www, appears to be gone. If anyone can find the PDF, please email it to me and I will insert it here.
There is an AIC which describes how this works – unfortunately it’s in the EAD system and the link below is likely to expire.
http://www.ead.eurocontrol.int/eadbasic/pamslight-085E3F942AF1FEEBA5716725F62A17D9/7FE5QZZF3FXUS/EN/AIC/P/072-2008/EG_Circ_2008_P_072_en_2008-08-14.pdf
If the link fails, the document is: AIC 72/2008, Compatibility of airborne VHF receivers with offset carrier systems
Go to http://www.ais.org.uk
Select IAIP from the ribbon menu
Then select Aeronautical Information Circulars from the sidebar menu
Choose Pink (P) – Safety related topics from
Scroll down to 2008 and locate: Compatibility of Airborne VHF RTF Receivers with Off-set Carrier Systems – 72(P144)/08