Quad Peak Detector Board; Figure 4-7. Power Supply Board Block Diagram (8520C) - Honeywell Chadwick-Helmuth 8500C Maintenance Manual

The power supply contains a closed-loop regulator, which keeps the output voltages constant for
varying input voltage and load. An optoisolator feeds back the output voltage across the isolation
barrier. A light emitting diode (LED) indicates when power in on.
DIODE
12 TO 28 VDC
BRIDGE

Figure 4-7. Power Supply Board Block Diagram (8520C)

4.2.2.4

Quad Peak Detector Board

The quad peak detector board contains four circuits identical to the pulse detector described on the
digital board, one per syn input. Since these circuits are adaptive, this parallel architecture allows rapid
measurement among channels without adaptation latency.
OPTO-ISOLATOR/
REGULATOR/
LED
PWM
STEP-DOWN
TRANSFORMER
8500C/8500C+ System Maintenance Manual 4-13
Detailed Description
RECTIFIER/
+5 VDC
FILTER
RECTIFIER/
+12 VDC
FILTER
RECTIFIER/
-12 VDC
FILTER