Installation
ETIC - MR1200 - USER MANUAL - 908709-02
Page 17
The PTT signal is derived simply by closing a pair of contacts operated by the changeover button :
+5V
PTT
Board
Push to talk button
2.8.3. MICROPHONE connection
The external microphone signal is amplified and filtered (low-pass filter, IC3-A + C18 + R21 + P3 +
C16).
If necessary, the signal level can altered by modifying resistor R21 (consult ETIC).
2.9. T/R power supply
The transceiver connected to the MR1200 should have an external power source.
For sleep mode operation the V
REG
output can then be used to control a T/R power supply relay.
MR1200
TRANSCEIVER
RX
TX
GND
+ V
Vreg
Содержание MR1200
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