跳转到主内容
帮助

当前版本: Philip Le Riche ,

文本:

-From research elsewhere it appears that on domestic devices at least, beneath each key there are one or two contacts each cosisting of a conductive rubber pad which makes a connection between two circuit board traces, like the buttons on many feature phones, calculators and other small devices. So they are necessarily normally open.
+From research elsewhere it appears that on domestic devices at least, beneath each key there are one or two contacts each cosisting of a conductive rubber pad which makes a connection between two circuit board traces, like the buttons on many feature phones, calculators and other small devices. So they are necessarily normally open. I would guess that high end devices such as an electrically operated church organ keyboard would have a more sophisticated switch mechanism, as conductive rubber pads tend to wear out.
-(For the record, the fault on this devices was that one of two ribbon cables, each connecting half the keyboard to a keyboard scanning board, had been inadvertently connected the wrong way round.)
+For the record, the fault on this devices was that one of two ribbon cables, each connecting half the keyboard to a keyboard scanning board, had been inadvertently connected the wrong way round.

状态:

open

原帖由: Philip Le Riche ,

文本:

From research elsewhere it appears that on domestic devices at least, beneath each key there are one or two contacts each cosisting  of a conductive rubber pad which makes a connection between two circuit board traces, like the buttons on many feature phones, calculators and other small devices. So they are necessarily normally open.

(For the record, the fault on this devices was that one of two ribbon cables, each connecting half the keyboard to a keyboard scanning board, had been inadvertently connected the wrong way round.)

状态:

open