indicator disk造句

A dial known as the " indicator disk ", also on the left side, is turned to the first letter in the message.
If the driver does acknowledge the warning, the indicator disk changes to yellow and black, to remind the driver that he has acknowledged a warning.
The first letter of the ciphertext is entered via the indicator disk, and the power handle is operated, advancing the key wheels and printing the decoded letter on the paper tape.
A set of " intermediate gears " advances the key wheels by one position, and a locking arm latches into the drum to prevent a second encoding until the indicator disk is adjusted for the next letter.
It's difficult to find indicator disk in a sentence. 用indicator disk造句挺难的