Collection Item 

Burroughs C3260
Brand:  Burroughs. 
Model:  C3260. 
Origin:  Japan. 
Introduction:  1971. 
Type:  Big basic desktop calculator. 
Functions:  4Basic function, addonly memory and 16 digit result mode for multiplication and division, no constant. 
Display:  8 digit + Sign individual big Itron tubes. 
Keyboard:  17 reedswitch keys, Mem/16 digit mode, Clear Memory and ON/OFF switch. 
Main chips:  Rockwell NRD2256, DC1152, ACM1156, AU2271C and Hitachi HD3113P with date codes Oct/70, Feb/71, Mar/71, Mar/71 and Feb/71, respectively, very early!. 
Logic comments:  Based on the Sharp EL160
architecture with slight differences on the keyboard layout, but functionally identical. First implementation of LSI technology in a calculator with 4 chips manufactured by Rockwell but
designed by Sharp, each counting 1875 electronic components. Also used in Sharp EL8, Sharp QT8B, Sharp QT8D and other OEM versions. Keyboard has an unusual layout in order to
minimize the key count. Key description: 09 and point: Numerals and decimal point keys. ÷X (DivideMultiply): Use to divide or multiply if you complete the operation with := or += respectively, see examples below. += (AddMultiply): Use to add or complete a multiplication. := (SubstractDivide): Use to subtract or complete a division. C (Clear): Clears the calculator or return from the memory content. Diamond key: Shows the memory register or the 8 right digits in a multiplication or division exceding 8 digits, depending on the Mem/16 switch. Black + (Memory add): Adds to memory register, only if Mem/16 is in "Mem" position. In "16" position has no function. Mem/16 (Memory mode): Switchs between memory mode and 16 digit mode for multiplication and division. CM (Clear memory sliding switch): Clears the memory register. Simple operation examples: a) To compute 2+3 enter 2 += 3 += b) To compute 23 enter 2 += 3 := c) To compute 2*3 enter 2 ÷X 3 += d) To compute 2/3 enter 2 ÷X 3 := You can read a complete article about the Burroughs C3260 here, from OldCalculatorMuseum.com. 
Remarks:  Very robust and heavy construction, big Itron display, very clear and readable, no battery support. 
Size:  9.84 x 6.10 x 3.35 in, 250 x 155 x 85 mm. 
Condition:  (9.9/10) Immaculate, better than you can see in this pictures, working. 