Minoru Nakano

The electric field changes and UHF radiations caused by the triggered lightning in Japan

The electric field changes, the magnetic field changes, and UHF radiation were observed during the rocket-triggered lightning experiment in winter storms. A remarkable discrepancy is noticed between electromagnetic field changes of flashes triggered with a rocket and an isolated wire that struck a power tower and flashes with a rocket and a grounded wire. Flashes to tower have a distinguishable first pulse of a large amplitude, which, we speculate, occurs at the moment of attachment of a downward leader to the tower. The UHF radiation measurements indicate that the triggered lightning process starts with a pulse series resembling a negative stepped leader. The electric field change records of rockettriggered lightning in winter storms do not show the presence of rapid field variations typical for return strokes in natural cloud-to-ground flashes.

Color Adaptor for Industrial VTR by a Line-Sequential Color Difference Signal System

工業用VTRのカラー化の一方式として, NTSCカラー信号を線順次色差信号に変換して録画するカラー変換装置を開発した.これを用いれば, この種の白黒用VTRの機構部を改造する必要がなく, 位相ひずみの多い伝送系でも色相の安定なカラー画像が再生できる.

A Study on the Slow Scanning Television System

動きの遅い物体とか書画の映像をテレビ伝送する場合には帯域幅をいちじるしく狭くできる.特に, 横書き文書は縦方向に行間の空白があり, 絵素数は横方向ほど多くを必要としない.この点に着目して, 縦方向に線走査し狭帯域化を試みた (帯域幅200kc, 長残光性受像管使用).また, 1画面走査20秒, 帯域幅3kcでもビジコンが使用できることを示した.