Скачать или смотреть Safetran Type 3 "E-Bell" Digital Audio Crossing Sounder

I know this is a little different from what I usually cover, but as an audio/electronics guy, I found this rather interesting. Just recently, I have noticed that many railway level crossings around Melbourne and even all around Australia are ditching the traditional mechanical bells and replacing then with speakers that playback a synthetic, digital recorded bell sound from a microchip. These are commonly known as "electronic bells" or "e-bells" and are currently being produced by a number of signalling companies. This particular model was manufactured by Safetran Systems Inc and consists of a small circuit board containing a digital audio chip and amplification circuit as well as an outdoor horn speaker. When the crossing is activated by an approaching train, it imminently sends electricity to the unit and begins playing continuously until the crossing relay shuts the signals off after the train has passed.