the micro compet from 1969 was a breakthrough, the first
use of LSI (large scale integration) enabled this machine to be
substantially smaller than its predecessors and those of other
manufacturers like the anita. although not yet
compact enough to be battery powered, there is a retractable carry handle
in the top so the unit could easily be transported in a briefcase.
units like this, with the use of new LSI, marked the start of the calculator
wars. a time when many older manufacturers like busicom and sumlock
were forced out of business.
this model powers up scrambled. the digits dance and flicker
erratically. after a couple of presses of the C key, it calms down
and is prepared to calculate. calculation proceeds like most desk
calculators where the operation is postfix. for example 2+3 is
entered as 2,+=,3,=+ and 23 as 2,+=,3=. multiply
works in the normal way, except divide is rather strange. it shares the
same key as multiply, and to perform a divide you finish with the red
subtract button. for example 2*3 is entered 2,*/,+= but 2/3
is 2,*/,=.
the display is rather unique and of a highly styled design. zero is
only half height (like early casios). it consists of 8 individual 8
segment (plus point) Itron display tubes. there is a special ninth tube on
the right capable only of a minus sign and a dot (which indicates
overflow).
compared to models of this period, this one calculates very fast. i see
only momentary delay for multiply and divide operations. some models could
easily take half a second. 
