Broadcast Electronics AM-2.5E, Руководство пользователя

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1-34. To provide an operational example, antenna 1 is designed to operate with power level 2.
When antenna 1 is connected to the transmitter, a HIGH status signal is applied to
optical coupler U7. U7 outputs a HIGH to switch S1. S1 is a four-section SPST switch.
The S1 switch sections are assigned the following power levels: 1) power level 2, 2) power
level 3, 3) power level 4, and 4) power level 5. The switch is programmed by closing the
switch sections for the power levels which are acceptable for the antenna 1 system. The
outputs of programming switch S1 are applied to a control network consisting of: 1) a
power level 2 circuit, 2) a power level 3 circuit, 3) a power level 4 circuit, and 4) a power
level 5 circuit. Each power level control circuit contains an OR gate to monitor the status
of the antenna systems and an AND gate to monitor the status of the selected power level.
1-35. With S1 programmed to operate with power level 2, the HIGH from U7 is applied to OR
gate U12A. U12A will output a HIGH to NAND gate U20A. With power level 2 selected,
a HIGH from BCD-to-decimal decoder U18 will be applied to U20A. U20A will respond
by routing a HIGH to OR gate U21C. U21C will output a HIGH to OR gate U13B.
Programmable jumper J1 is provided to disable the antenna interlock circuit. With the
antenna interlock circuit enabled, U13B will output a HIGH to NOR gate U24A and AND
gate U22B. With no mute or off commands present, U24A will output a LOW to disable
antenna conflict indicator driver Q16. With a closed interlock system and no ac failures
or failsafe conditions present, U22B will output a HIGH operate command to enable the
transmitter.
1-36.
REMOTE CONTROL.
The transmitter control functions, status indications, and metering
signals are designed for remote operation. Control functions require a +5 volt to +15 volt
dc signal to activate the function. Status indications will output a LOW (0 volts) when
active. The remote meter indications can be programmed for +5 volt or +2.5 volt
full-scale meter operations. The circuitry may be interfaced to any type of remote control
unit.
1-37. Remote control of the transmitter is enabled or disabled by remote/local switch S4. S4
enables remote control operation by applying a positive voltage to optical couplers U1
through U6, U32/U33, and U53. S4 disables remote control operation by applying a
ground to the couplers. The remote position allows both local and remote transmitter
control. The local position allows only local control of the transmitter. The remote control
inputs and outputs are RFI filtered on the motherboard for maximum reliability.
1-38.
POWER ON.
A transmitter power on operation initiates a sequence to determine if all
the interlocks are closed and the remote control unit is operational. RF output power
from the transmitter is enabled by commands from the power level 1 through power level
5 switch/indicators. Each power level switch/indicator provides a one-button power on
start command and configures the transmitter for a specific power output level. Each
switch/indicator will illuminate as selected to indicate the command has been received
and stored by the controller power control circuit.
1-39. Transmitter power is enabled when a power level switch/indicator is activated. For
example, when the ECU power level 2 switch/indicator is depressed, a HIGH is applied to
priority encoder U14. When a remote power level 2 command activated, a HIGH is
applied to optical coupler U4. U4 will output a HIGH to U14. U14 analyzes power level
and off commands to determine priorities when two switches are operated simultaneously.
The off command is assigned the highest priority. When the power level 2 command is
received, U14 will output a binary number to latch U15. U15 outputs the binary number
to latch U17. U15 and U17 operate in association to provide the appropriate output
timing of the binary number to the antenna interlock circuit and to the power control
circuit.