Texas Instruments

Model: SR-40 LCD
Battery: 2 x AA
Adapter: NO
Year: 1981
Chip: TP0320
Manual:            
Info: The extremely rare SR-40 LCD (1981) calculator produced in Brazil is an interesting model, as at first glance it looks very similar to the European version of the TI-30 LCD. However, a few differences set it apart. One of the most noticeable differences concerns the keys: while the European TI-30 LCD features the **N!** (factorial) key, the Brazilian SR-40 LCD has the **x!** key, a detail that might reflect slight variations in functionality or target use. Another notable difference is the design of the battery compartment. The SR-40 LCD uses two AA batteries, but the compartment cover requires a coin to be opened, unlike the sliding cover of the European TI-30 LCD. This feature probably represents an adaptation for greater durability or security in battery replacement. These small variations between the models highlight production differences between different markets, making the SR-40 LCD a particularly rare and interesting piece for vintage calculator collectors.

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