Explanatory notes
… apparatus (e.g., developing equipment) falls in Chapter 90 . (E) Telephonic or Telegraphic Switching … . (l) Telephone call registers and counters ( Chapter 90 ). (m) Carrier-current and other transmitters and … a functional unit within the meaning of Note 3 to Chapter 90 ( Chapter 90 ). (n) Calculographs (time recorders) ( …