Nepro Memotron Alarm Watch (1972)

Calibre ETA 2671 Automatic | 17 jewels | Diameter 

In 1972 Nepro Memotron was introduced @ Baselworld as being world's first mechanical watch with an electronic alarm. The calibre ETA 2671 (used in ladies watches) automatic movement was used in order to make space for the world's smallest acoustic generator called the MicroBuzzer 500.

Nepro Elevox & Memotron II

The other model Nepro introduced in 1972 was the Elevox. A mechanical  watch (Cal. FHF 69) with an electronic alarm which resonates through the crystal of the watch. One year later a new Memotron was issued containing a fully battery operated dive-balance movement by Porta (Cal. 651) and an electronic buzzer. 

Swiss patented

At the time Nepro introduced their Memotron and Elevox, the Swiss Made signature wasn't granted yet so both dial and case back are signed Swiss patented.