Category:Vacuum tubes on stamps

Media in category "Vacuum tubes on stamps"

The following 2 files are in this category, out of 2 total.

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  The Soviet Union 1968 CPA 3680 stamp (One of the First Soviet Radio Tubes and Old Building of Nizhny Novgorod Radio Laboratory).jpg 964 × 679; 120 KB
  
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  The Soviet Union 1968 CPA 3680 stamp (One of the First Soviet Radio Tubes and Old Building of Nizhny Novgorod Radio Laboratory).png 964 × 679; 1.85 MB