Rsdist Board (713-5003) - Hitachi 902 Service Manual

10.9 RSDIST Board
(1) Explanation of Circuit Board
This circuit board interrupts/distributes RS-232C signals of the ECPU237 and EMIO100
boards. The board is provided with the current loop function for the host and permits
changeover through DIP switch setting.
The board is also provided with an alarm buzzer, whose volume can be adjusted with
VR1.
(2) External View
Buzzer volume adjustment
(270)
Setting of SW1
No. 1
No. 2 to 4
( )
115
Buzzer FG
terminal
OFF: RS-232C
Normally OFF
10 - 45
ON: Current loop