Big O: Presenter, Five FM
james O Neill: Programme Manager/Controller, Southend Radio 105.1
Mark O Sullivan: Presenter, Touch Radio (Tamworth)
Anna O'Brien: Programme Manager/Controller, Winchester Hospital Radio
Matt O'Brien: Head of News, Frequency
James O'Brien: Presenter, LBC 97.3
Roni O'Brien: Presenter, Solar Radio
Kirsten O'Brien: Presenter, BBC Radio 7
Tom O'Brien: Producer, Magic 1152 (Manchester), Key 103, CSR
Simon O'Brien: Presenter, City Talk 105.9
Andrew O'Brien: Programme Manager/Controller, RaW 1251AM
Gareth O'Callaghan: Presenter, RTÉ 2fm
Christian O'Connell: Presenter, Absolute Radio
Dan O'Connell: Presenter, Galaxy (Yorkshire)
John O'Connor: Sales/Commercial Director, Q97.2
Kev O'Connor: Presenter, Future Radio 96.9
Gordon O'Connor-Read: Presenter, Rare FM
Kenny O'Dea: , Radio Warrington
Malachi O'Docherty: Presenter, U105
Tony O'Donnell: Presenter, 1548 Forth 2
Shane O'Donoghue: Presenter, RTÉ Radio 1
Shane O'Donoghue: Presenter, RTÉ 2fm
Donnach O'Driscoll: , Absolute Radio, dabbl
Sarah O'Flaherty: Presenter, 102.5 Clyde 1
Paddy O'Gorman: Presenter, RTÉ Radio 1
James O'Hara: Head of News, BBC Stoke
John O'Hara: Presenter, U105
Dermot O'Leary: Presenter, BBC Radio 2
Liam O'Leary: Presenter, BBC Somerset
James O'Mahoney: Presenter, CRMK
Andy O'Mahony: Presenter, RTÉ Radio 1
Eamon O'Neal: Presenter, BBC Manchester
Joe O'Neil: Presenter, Oxford's FM107.9
Rob O'Neill: Head of Sport, KCFM 99.8
Paul O'Neill: Presenter, BBC Cumbria
Louise O'Neill: Presenter, GU2 Radio
Miranda O'Neill: Presenter, Lloydspharmacy Live
Hazel O'Neill: Presenter, Radio Northwick Park
Rob O'Neill: Presenter, KCFM 99.8
Willie O'Reilly: Managing Director, Today FM
Damien O'Reilly: Presenter, RTÉ Radio 1
Ruth O'Reilly-Smith: Presenter, UCB UK
Dave O'Rourke: Presenter, Radio Tircoed
Rick O'Shea: Presenter, RTÉ 2fm
Dennis O'Shea: , Radio Enfield
Mark O'Sullivan: Presenter, Touch Radio (Warwick)
Mark O'Sullivan: Presenter, 107.1 Rugby FM
Danny Oakes: Presenter, Galaxy (Yorkshire)
Sharon Oakley: Presenter, 102.5 Clyde 1, 105.2 Smooth Radio (Scotland)
Chris Oakley: Presenter, Heart 103.4 Cheshire and North East Wales
Sharon Oakley: Producer, Breakfast Show, 105.2 Smooth Radio (Scotland)
Kevin Oates: Presenter, Palm 105.5
DJ Oblong: Presenter, BANG Radio 103.6
Peter "Ockels" Ockelford: , talkSPORT
Joe Odber: Head of News, Northsound 2, Northsound 1
Melvin Odoom: Presenter, Kiss 100
Andy Ofield: Presenter, 103 The Eye
Jeremy Ogden: Presenter, The Bay (Lancs/Cumbria)
David Ogg: Station Manager, Nevis Radio
Ian Ogg: Presenter, Your Radio
David Ogg: Presenter, Nevis Radio
Ayumi Okada: Head of Creative, Radio Sonar
CK Okereke: Presenter, Trax FM (Bassetlaw)
CK Okereke: Presenter, Trax FM (Doncaster)
Dave Oldacre: Digital Editor, 96.3 Radio Aire
Sally Oldham: , Red Dragon FM
Leon Oldman: Presenter, Sunshine Radio (FM)
Richard Oliff: Presenter, 102.3 HFM
Ewen Oliver: Presenter, Nevis Radio
Derek Oliver: Presenter, Total Rock
Chris Oliver: Presenter, CRMK
Marlene Oliver: Presenter, Wythenshawe FM
Keith Oliver: Presenter, Apple AM
Mike Ollivier: Chairman, L&D Hospital Radio
Les Oman: Presenter, Argyll FM
Anwar Omer: Presenter, Radio XL 1296 AM
Mandy Oneale: Presenter, HSBC Live! Radio
Sue Onions: Presenter, 103 The Eye
Rachel Opoku: Presenter, BANG Radio 103.6
Brett Orchard: Managing Director, Star 107.5
Steve Orchard: Presenter, Oak FM (Hinckley)
Steve Orchard: Presenter, Ridings FM
Steve Orchard: Presenter, 106.6 Smooth Radio (East Midlands)
Ellen Orchard: Presenter, Streaming Radio
Steve Orchard: Presenter, Rother FM
Mick Ord: Programme Manager/Controller, BBC Merseyside
David Ord: Presenter, East Herts Hospital Radio
Kat Orman: Presenter, Reading 107fm
Kat Orman: Presenter, HSBC Live! Radio
Ian "Big Stix" Ormondroyd: Presenter, Pulse 2
Guy Ornadel: Presenter, Ministry of Sound Radio
Tim Orr: Head of Creative, Heart 96.3 Bristol
Tim Orr: Copywriter, Red Dragon FM
Paul Orr: Presenter, Citybeat 96.7 102.5FM
Nick Osborne: Presenter, Bright FM
Natalie Osborne: Presenter, 107.8 Radio Jackie
Ben Osborne: Presenter, totallyradio
Natalie Osborne: Presenter, Epsom Hospital Radio
Ben Osborne: Presenter, NME Radio
Mike Osborne: Programme Director, Heart 103.1 and 102.8 Kent
Cliff Osbourne: Programme Manager/Controller, Radio Caroline
John Osbourne: , Gold (London)
Everton Osbourne: Presenter, BBC Leicester
Liz Osbourne: Presenter, 102.3 HFM
Segun Oshin: Presenter, GU2 Radio
Jon Osterland: Presenter, 97.4 & 107.9 Afan FM
Annie Othen: Presenter, BBC WM
Annie Othen: Presenter, BBC Coventry and Warwickshire
Otto Mation: Presenter, U105
Michael Otton: , The Bay 102.8 (Poole/Bournemouth)
Stephanie Otty: Head of News, The Pulse of West Yorkshire, Pulse 2
Debbie Ousbey: Presenter, 105.4 Real Radio (North West)
Rob Ousbey: Presenter, CUR1350
Carice Ovenden: Presenter, Xpression FM
Over Nite: Presenter, Six FM
Chris Overend: Managing Director, Peak FM
Overnight: Presenter, Channel 103 FM
Overnight: Presenter, Channel 103 FM
Overnight: Presenter, The Beach
Dave Owen: Programme Manager/Controller, 107.8 Radio Jackie
Sue Owen: Station Manager, BBC Stoke
Dave Owen: Presenter, 107.8 Radio Jackie
Robbie Owen: Presenter, Hertbeat fm
Gareth Owen: Producer, BBC Guernsey
Johnny Owen: Presenter, Signal 2
Jeff Owen: Presenter, BBC Nottingham
Jamie Owen: Presenter, BBC Radio Wales
Garry Owen: Presenter, BBC Radio Cymru
Gwilym Owen: Presenter, BBC Radio Cymru
Jennifer Owen: , Mercia
Darren Owen: Presenter, William Hill Radio
David Owen: Presenter, Keith Community Radio
Michelle Owen: , 97.4 & 107.9 Afan FM, Xtreme Radio 1431AM, Xtreme Radio 1431AM
Judy Owen: , 102.5 The 'Bridge
Kelly Owen-Simpson: , Moorlands Radio
Trevor Owens: Head of Sport, BBC Hereford and Worcester
Jacqueline Owens: Presenter, Oban FM
Trevor Owens: Presenter, BBC Hereford and Worcester
Paul Owens: Programme Manager/Controller, Time 106.6
Barry Owler: Presenter, Q97.2
Chris Oxlade: Presenter, Mercury FM
James Oxley: Presenter, The Beach
Simon Oxley: Presenter, BBC Three Counties
Ray Oxley: Presenter, Auckland Hospital Radio
Ray Oxley: Presenter, Radio North Tees
Ali O`Brien: Presenter, BBC Manchester
Ulick O`Connor: Presenter, Newstalk
Brian O`Neill: Head of News, Gold (Northampton), Heart 96.3 and 102.6 Essex
Jerry O`Sullivan: Presenter, Newstalk
Ciaran O`Toole: Station Manager, 96.3 Rock Radio (Scotland)
Ciaran O`Toole: Presenter, 96.3 Rock Radio (Scotland)
Positions given are generic, and should be used as an indication only.
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