![Brother 827R Calculator](https://vintage-calculator.com/wp-content/uploads/2023/10/bro827r.jpg)
The Brother 827R is a handheld calculator from 1974. It measures about 78mm x 127mm x 17-22mm (width, height, depth) and weighs 150g without batteries. The case is two-piece smooth plastic in a cream color, with grip ridges on the sides for easy handling. A large red display filter wraps around the front to improve readability of the small digits on the 8-digit LED display. An additional LED indicates when memory is in use.
Inside, the 827R contains a Texas Instruments TMS0603 processor chip, two SN75494 display driver chips, a 9-digit bubble lens LED display, two transistors, five diodes, six capacitors, no resistor arrays, 11 resistors, and a transformer. The keyboard connects to the main circuit board via 17 wires.
![](https://vintage-calculator.com/wp-content/uploads/2023/10/bro827rs.jpg)
Power comes from three AA batteries or an optional AC adapter. Rechargeable NiCd batteries can also be used. Functions include the four standard arithmetic operations, percentages, and a 4-function memory with summation mode. Automatic constant, input overflow suppression, and overflow/error indication are implemented in the logic. There is no squared function.
In daily use, the 827R feels well-built, with nice “clicky” keys. The two-step clear button and summation switch add convenience. Downsides include the small display, lack of squared, and some unrecoverable errors. But overall the 827R provides the expected features for a mid-1970s handheld calculator in an easy to use package.