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H E O R Y
Over/Under Voltage Shutdown
•
If +5 V power output is excessive (compared to a +5 V reference
voltage), an op amp and transistor shut down the +5 switcher
circuitry.
•
If the battery voltage drops below approxi10 V, the
complete system shuts OFF to avoid totally depleting and
ruining the battery.
DC ON/OFF
A rear panel ON/OFF SPST toggle switch controls a small voltage
and current to an op amp that allows a FET to conduct current to
both +5, +12 V and -12 V switching circuits.
+5 V, +12 V, and -12 V DC-to-DC Converter
•
A circuit senses load requirements and automatically adjusts the
duty cycle to maintain a reg5 V, +12 V and -12 V output.
•
The circuit can run on its own internally generated clock signal,
or it can accept external input to achieve its 100 kHz switching
frequency.
LED/AC Operation
The front panel green LED indicates AC mains is connected, and the
AC mains switch is ON.
Antenna Systems
The telemetry antenna system collects radiated RF energy from a
transmitter and delivers that energy to a receiver. Because the
received power from a transmitter decreases as the distance to the
antenna increases, antenna systems must be designed so that a
transmitter is never very far from a receiving antenna.
Antenna Distance and Power Loss
The distance to an antenna is not only the physical distance
measured in feet, but can also be an equivalent RF distance
measured in power loss.
