Antique vacuum tube

At the SK0QO Field Day on Sep 4 I met Hiro, 7K1PYG (to the right) and Hisashi Ohtsuka. I have met Hiro earlier some years ago. Also that on a field day, close to the Technical Museum in Stockholm, when Hiro was QRP´ing on 20 m I think. Hiro is well known as biking with his QRP station in Japan. Besides ham radio he practises research about production of silicon carbide semiconductors. Hisashi Ohtsuka is a researcher in the UEC Communication Museum in Tokyo. His special interest is in vacuum tubes and the museum has a huge collection of tubes. He was here in Sweden to collect on loan from the Technical Museum a very unique old tube. A von Lieben tube used before the radio tubes were invented. This rare tube is saught after by collectors. In an auction 2003 one tube was sold for 14,500 USD, a sales record for a tube. The tube is very fragile and Hisashi told me that they have prepared a special exhibition stand that will prevent the tube to be destroyed from earth quake shakings. Below he showed me an article about the tube collection in the japanese CQ Ham Radio magazine.

This is the Lieben tube before packing it for transportation to Japan.


Michael Barrie said…
My great, great-uncle was Eugene Reisz. I believe he co-invented the Lieben tube. Would be fascinated to hear more about him. Did he emigrate to the US and die there? Michael Barrie