Hi ATPMBA,
The FRTOL can be issued as a stand-alone licence. I would recommend some training prior to test. The syllabus of training for the UK theoretical written PPL Communications examination and practical Communications test, is based upon CAP 413 “The Radiotelephony Manual”, the UK AIP, the ANO and AMC 1 FCL.210 and FCL.215 to Part-FCL.
The written RTF Communications exam is a multiple choice paper for which you are allowed one hour. The practical is conducted on the ground and is a scenario based exercise ('flight') which takes about an hour also.
As an ICAO licence holder who has been tested in English, you will be exempt the written exam, but probably won't be exempt the practical from what you've said - it depends on your experience. More detail in CAP 804.
Do I need to hold an EASA PPL or higher?
No. It can be issued as a stand-alone licence. More information can be found in CAA
CAP 804, Section 6.
Do I need to hold a medical certificate?
Not if you just want the FRTOL issued. If you would like an EASA pilot's licence issued, then you will need a EASA medical.
I'm on the list of examiners which is available on the CAA website:
RT Examiners: List of Authorised Flight Radiotelephony Operators Licence Examiners | Publications | About the CAA
FRTOLs are now issued as lifetime licences. CAA charge £73 for issue of a standalone FRTOL. If it's included as a part of a EASA licence application, there is no additional charge for issue of a FRTOL.
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