Название файла: Seaward PV150 Manual.pdf
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Количество загрузок: 1920
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Years ago, to help the sailor determine his location, the Lighthouse Board (which was in charge of lighthouses from 1852–1910) issued an order to have each lighthouse painted in different colors and/or designs. Early on, they built multiple lights (that is, two or three together.) This was one way to help the sailors at sea determine their location, but it was very expensive. Can you imagine being a lighthouse keeper and having to fire the cannon every hour when there was fog? The first one was used in 1719 at Boston light and it was, of all things, a cannon. Observations: 1. Our 3 Tek DPO3054s have failed and had to be sent back for repair 3 times, 2 went black suddenly, one USB burn out. No problems with 5 DLMs.2. Our Tek DPO3054 knobs have gotten noisy to the point of making the DPO3054 nearly useless. The invention of the Fresnel (pronounced “Frey Nel”) lens in 1822 was probably the most important discovery in lighting technology. As well as enabling man to produce an unlimited number of flashing combinations, it also intensified (brightened) the light so it could be seen at greater distances.