There's a bird, which I can't see, singing somewhere in the garden. It sounds to be high up in some tall hedge or tree. The 'song' is a constantly repeated phrase on one high note : 'tinker-tinker-tinker-tink' [pause of a few seconds] 'tinker-tinker-tinker-tink' [pause again] and so on
Both Great tit and Chaffinch can make a "chink" sound. A Great Tit has been likened to a rusty bicycle - sounds like "teacherteacherteacher". The BBC website has birdsong which you can listen to
You have just described a Great Tit song. Only other likely one is a chaffinch call which is pink pink pink but not repeated ad infinitum as per the Great Tit- so pretty definitely Great Tit- it always fools a lot of people in the spring
Hmm. Sounds like it must be a great tit, if the bird keeps repeating the same phrase. This bird was not as much like a 'rusty bicycle' as the bird in the RSPB recording. It was more like the coal tit's first phrase on the RSPB recordings, repeated incessantly but with a marked pause between repeats .
Perhaps it's great tit which hasn't learned its full range yet, or it's one with a local dialect ( East Anglian here) ;) !