DATAMATH  CALCULATOR  MUSEUM

Toshiba BC-1011

Date of introduction:  1971 Display technology:  Fluorescent
New price:  115.000 (US$ 370) Display size:  10
Size:  10.2" x 7.2" x 3.5"    
Weight:  4 pounds 9 ounces Serial No:  452830
Batteries:  n.a. Date of manufacture:  mth 12 year 1970
AC-Adapter:  220V Origin of manufacture:  Japan
Precision:  14 Integrated circuits:  Toshiba T3019, T3026, 20*SSI-IC's
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner

If we trace the timeline of electronic calculating devices we will notice the introduction of transistor based calculators in 1964 and a quick integration of these transistors into integrated circuits within some years. 

This Toshiba BC-1011 is a hybride using two different technologies:

The first use of LSI-IC's (Large-Scale-Integration Chips) manufactured by Toshiba.
The last use of SSI-IC's (Large-Scale-Integration Chips) in a elctronic calculator.

Dismantling the BC-1011 reveals three different printed circuit boards (PCB's):

The upper half of the calculator with the power supply and a rigid keyboard using Reed-contacts excited by small magnets attached to each key. BC-1011_1.jpg (207344 Byte)
The main PCB with the two LSI-IC's manufactured by Toshiba and the 10-digit VF-Display. 

BC-1011_3.jpg (184650 Byte)

The second PCB with an overall of 20 SSI- and MSI-IC's:
9 TM4004: unknown function
1 TM4005: 2 AND-OR gates
4 TM4103: 4 D-Flip-Flops
1 TM 4106: 60-bit Shift register
1 TM 4108: unknown function
2 TM4306: unknown function
2 uPD12A: unknown function
BC-1011_2.jpg (279978 Byte)

The predecessor Toshiba BC-1212 was introduces in 1970 and gives comparable specifications. It lacks the LSI-IC's (Large-Scale-Integration Chips) and uses instead 38 of the SSI- and MSI-IC's.

The BC-0802 introduced soon after the BC-1011 makes already use of a single-chip calculator circuit.

If you have additions to the above article please email: joerg@datamath.org.

Joerg Woerner, March 6, 2004. No reprints without written permission.