mememuseum, 8 months ago This one in particular is one of the later 50s models that does direct subtraction. The earlier ones don’t have the updated mechanism and you have to clear the unit to switch between subtraction and addition which makes them less useful for this.
This one in particular is one of the later 50s models that does direct subtraction. The earlier ones don’t have the updated mechanism and you have to clear the unit to switch between subtraction and addition which makes them less useful for this.