The Japanese amateur radio company Tokyo Hy-Power, well known for its high power linears for HF and VHF, has ceased trading
Tokyo Hy-Power Laboratory was founded in 1975 by Nobuki Wakabayashi JA1DJW in Saitama Prefecture near Tokyo, Japan. Their initial products were antenna couplers for HF bands such as the HC-500 and HC-2500.
In 1977, Tokyo Hy-Power Labs, Inc. was formally established as a developer and manufacturer of linear amplifiers, antenna tuners, etc. for radio amateurs. One of their early products, the HL-4000 linear amplifier using 8877/3CX1500A7 by EIMAC, was the first real HF band high-power linear of its kind in Japan.
As HF mobile operation grew in popularity, they developed fully-transistorized wide-band linears for mobile use such as the HL-200B and HL-400B.
In 1984 they started to manufacture RF power products for the industrial market. They developed RF switching mode technology used in 13.560 MHz RF power generators as well as other industrial and medical use products such as pulse high power and ultra wide band amplifiers.
In recent years they developed 3 KW VHF RF power generators together with a fast reacting auto impedance matcher used in the semiconductor manufacturing fabrication plants for advanced LSI chips.
Hamlife report in Japanese 24 December 2013 - http://www.hamlife.jp/2013/12/24/tokyo-hy-power/
Hamlife report in Google English - http://tinyurl.com/Hamlife-Tokyo-Hy-Power
The company's Japanese language website was at - http://www.thp.co.jp/
The site is no longer available but a copy taken in August 2013 can be seen - https://web.archive.org/web/20130822211226/http://www.thp.co.jp/
At the time of writing the English language website was still available - http://www.tokyohypower.com/
Japan once had more radio amateurs than any other nation but since 1996 the hobby has been in sharp decline with the number of amateur radio stations falling by over 65% - http://www.speroni.com/MPT/JA-Stations.html