Image Colnect-3169-014-De-Forest-Audions.jpg
(1024 x 641 pixels) |
Type: stamp Issuer: United States Date: 1973 Denom: ?
Visibility: public Image owner: none airmail 7/10/1973 11c multi issue=Progress in Electronics d=two De Forest audions unwmk perf=11 Crops No visible images cropped from this one. Measurements Resolution is unknown. Source Source name: Colnect File URL: http://i.colnect.net/b/3169/014/De-Forest-Audions.jpg Uploaded May 19, 2016, 3:42 pm by Stan Shebs |
