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use a 9-volt battery, the quickest way to get
this data is to connect it to one. The cam-
era owner connected a conventional battery
through an RRAmpmeter to the battery. He
read 8.6 volts at 0.12 amps.
We’ll use those numbers to figure out what
value of resistor (R1) to use to connect the
camera to our power supply. The purpose
of this resistor is to drop the voltage down to what the camera
wants when the camera is drawing its operating current.
First, we figure out how much voltage we need to drop across
the resistor. The camera seems happy at 8.6 volts and the
power supply will deliver 14.3 volts. Thus, the resistor needs to
drop 5.7 volts (14.3 volts – 8.6 volts).
5: DCC input waveform to power supply – 14.65 volts
“track voltage”.
5
index contents