Vintage bulgarian calculator Elka 51 late 1970's 12 digits

Description

Vintage 1970's 12 digit Desktop 220V Electronic Calculator "ELKA 51"
The ELKA is a Bulgarian brand of electronic calculator, developed by the Central Institute for Computation Technologies(bg) and built at the Elektronika factory in Sofia. The name is a contraction of
ЕЛ
ектронен
КА
лкулатор, or "electronic calculator", and the word "
elka
" in the Bulgarian language has, by extension, become the generic name for a electronic calculator. The first model, the ELKA 6521, was introduced in 1965, and used germanium transistors and a nixie tube display. It weighed 8.5 kg and was allegedly the first calculator in the world to include a square root function.
In 70s. starts production on the lighter and more portable models
The model ELKA 51 is desktop calculator with ergonomic design, small dimensions, display is 12 LED element   (7 segment ) and 220 v power supply. The first generation ELKA 50 employs 4-bit microprocessor "CM-500".
These are the first 4-bit microprocessor series in Bulgaria and in the Eastern Bloc
. Based on them, "Elka 51" was produced, in which the number of MOS IC was further reduced from 10 to 4 pieces.
SHIPPING BY REGISTERED PRIORITY AIRMAIL , TRACKING NUMBER PROVIDED.
DELIVERY TIME TO EUROPEAN UNION : 5 - 10  BUSSINESS DAYS , REST OF WORLD : 10 - 25 BUSSINESS DAYS.