G'day R-J,

If you're used to finding your correct note on the keyboard, what about someting like a Hohner Melodica (or any of the Asian copies)? I don't know if Hohner still do the Melodica, but I still see 'ripoffs' of the instrument.

It usually has a 2-octave chromatic "keyboard" operating "free Reeds" (as in concertinas, mouth organs and accordions) so the individual notes are clear and simple ... good for picking up a specific pitch, without the confusion of harmonic effects. The better type for this use would be one with a plastic mouthpiece, rather than a length of flexible air pipe, which is used to allow playing in a seated position - looking at the keyboard).

I have seen these used by choirs and they seemed to fulfill most of the simplicity and size requirements you have ... and they don't need batteries. I keep one near my computer ... just to provided a diferent keying system from my normal "push-pull" concertinas or accordions ... to clear any mental 'log-jams' when I'm transcribing or writing a tune from the recesses of my mind.

Regards,

Bob