YOKOGAWA DL750 - Page 137

3-34
IM 701210-05E
Handling Precautions of the Earphone Microphone with a PUSH Switch
• Do not place the earphone microphone in a humid environment. Do not spill water on
the earphone microphone. This may cause a malfunction.
• Do not place the earphone microphone under direct sunlight, near a heater, or in hot
or dusty environments.
• Do not apply strong shock. Do not pull on the cord.
Circuit Diagrams of the Input/Output Section of the Earphone Microphone with a PUSH
Switch
Microphone Input
1
3
+5 V
Microphone
Amplifier
10 kΩ
10 kΩ
1000 pF
Earphone Output
32 Ω
2
3
Earphone speaker
Amplifier
33 Ω
33 µF
+
Switch Input
4
3
+3.3 V
Switch
220 Ω
10 kΩ
LCX14 or
equivalent
• Plug polarity signal
1234
1 Microphone input
2 Earphone output
3 GND
4 Switch input
Note
• The circuit diagrams above apply to the optional earphone microphone with a PUSH
switch (701951) that is sold separately. Operation of other earphone microphones are
not guaranteed.
• There is no protection circuit, because it is a dedicated input. Be sure to use the
dedicated earphone microphone by YOKOGAWA.
3.14 Connecting the Earphone Microphone with a PUSH Switch and Connecting the Speaker