It is well known. VEF, Eletrotehnika, Tondi Elektroonika and others. Also big biotech hub in Soviet times. AFAIK. Even the first soviet atomic bomb was partly build there ("Sillamäe").

I spare you the details for the Czech republic since this should be well known. They were always an industrial and manufacturing hub, even during German occupation in WW2. Airplanes, Tanks, guns, cars (Skoda!), machinery etc. Don't forget, they are a comparably small country.