Standard Horizon Quest GX1255S Service Manual page 23

LCD Contrast: 3.8 ~ 5.0 V
2.45 V (@13.8V)
Dimmer Control: 0 ~ 4.8 V
Key Beep: 500 mVp-p
Weather Alert: 2.5 Vp-p
Distress Alert: 5.0 Vp-p
MAX. 5.0 Vp-p
3.0 Vp-p
4.0 Vp-p
"H": 5.0 V
"L": 0 V
+5 V REG
RESET
90 msec
CNTL Unit
Circuit Diagram
Dimmer Control: 0 ~ 6.1 V
PTT "ON": 0 V
PTT "OFF": 5.0 V
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