Sharp EL-811

Date of introduction:  1971 Display technology:  Fluorescent
New price:  $379 Display size:  8
Size:  6.9" x 4.2" x 1.8"    
Weight:  20 ounces Serial No:  2007663
Batteries:  EL-84 (6*AA NiCd) Date of manufacture:  year 1972
AC-Adapter:  EL-81 Origin of manufacture:  Japan
Precision:  8 (Mult. 16) Integrated circuits:  Rockwell 10572, 10573
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner

Sharp Electronics Corporation introduced end of the year 1969 with the EL-8 the first portable, battery operated calculator. It uses the same technology as the earlier desktop calculator QT-8D

This EL-811 followed the EL-8 with about 18 month delay and uses a very similar architecture. Due to the big steps in IC-Technology (Integrated Circuits) the EL-811 sports more features (memory, 16 digit multiplication results) with only 2 IC's. From the complexity of the calculator it is very similar to the smaller Canon LE-10 featuring IC's from Texas Instruments.

Do get an impression about the valuable internal construction just take your time and watch the next five pictures carefully.

This picture gives you an idea of the sleek design of the calculator. EL-811_1.jpg (64978 Byte)
The display uses still the single tubes introduced with the EL-8.   EL-811_PCB2.jpg (19952 Byte)
This picture demonstrates the odd segmentation of the single tubes.  EL-811_disp1.jpg (9101 Byte)
Multiplication results with up to 16-digits could be displayed. EL-811_disp.jpg (7231 Byte)
The printed circuit board of the calculator brain shows the later 2-chip design developed by US company Rockwell together with the Hitachi display drivers. EL-811_PCB.jpg (101749 Byte)


The same housing was used again with the EL-8102 introduced in 1974.

horizontal rule

If you have additions to the above article please email:

Joerg Woerner, December 5, 2001. No reprints without written permission.