The word "JETB" is an acronym that may be difficult to spell out phonetically. However, using the International Phonetic Alphabet (IPA) it can be broken down. The first letter J is /dʒ/, pronounced as the sound in the word 'jump'. The second letter E is /ɛ/, pronounced as the sound in the word 'bed'. The third letter T is /t/, pronounced as the sound in the word 'top'. Finally, the letter B is /b/, pronounced as the sound in the word 'big'. Therefore, the correct phonetic spelling of "JETB" is /dʒɛtb/.