The indicating devices on the top of the rangekeeper give the rangekeeper operator at a glance the value of the hand inputs.
They allow him to adjust these inputs, in accordance with the information received by telephone from the source of the input, by turning the handcrank until the proper value is shown on the indicator.
A portion of the face of the rangekeeper is illustrated below, showing the principal hand input cranks and their associated indicators.

アメリカでさえ射撃盤への入力はクランクやノブによるハンドインプットを多用

だいたい、今の話題はメイン方位盤が使えない時に代替手段で射撃盤に入力する話
日本海軍はメイン方位盤が死んだら射撃盤も死ぬのか