Paradise Datacom HPAC-100-RM, Operation Manual

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3-10 Operations Manual: HPAC-100/125/150/200/250-RM SSPA
3 Operation of Stand-Alone Unit
Opto-Isolated Inputs: Two opto-isolated inputs are provided on the parallel
connector: mute configuration and fault reset. The mute pin can have two differ-
ent modes of operation depending on the internal DIP switch configuration, refer
to Table 3-19 and associated text. In one configuration, pulsing the mute pin low
for 100 milliseconds toggles the mute state. In the other configuration, the rear
panel mute input must be continuously grounded for unmute and left open for
mute. The changing of the mute status can be monitored using the contact
closure as described above. The second input is used as a fault reset. Holding
the pin to ground disables the reporting of faults. When the pin is released from
ground, faults will be newly detected and reported.
Voltage Outputs: The output power of the SSPA can be determined by the
differential voltage between the two power output pins on the parallel port.
Nominally, 5 volts corresponds to the rated output power with a scale of 0.1 V/
dBm. The output has an accuracy to 15 dB below the rated output power of
the unit.
The temperature pin has a voltage proportional to the highest unit tempera-
ture. 3.03 VDC corresponds to 303K (30°C) with a slope of 0.01V/K (0.01V/
°C).
Voltage Inputs: The attenuation level of the unit can be controlled by varying
the voltage to the attenuation control pin on the parallel port. This is accom-
plished by varying the resistance from this pin to ground. Internally this pin is
pulled up to 5V through a 10K ohm resistor. When calculating the external
resistor value use the voltage division equation of V
pin a
= ((R
external
/(R
external
+
10K))(5V). Every 0.1 V increment corresponds to 1 dB of attenuation with 2 V
corresponding to the maximum attenuation, 20 dB. This voltage must be
continuously held.
Serial Port Monitors and Controls
The HPAC-100/125/150/200/250-RM can be entirely controlled via the serial port. All
functions available on the front panel are also available through the serial interface.
Before communication can occur, the serial port must be configured properly by setting
internal DIP switches for the proper system address and baud rate along with changing
an internal connector on the processor board for the correct protocol, RS-232 or RS-
485. Also, the mode of control on line 3 of the OPS menu must be set to “REM” or the
serial command, set control mode to remote, must be sent.
Pin 4 of DIP switch 7 must be set to
OFF to control the attenuator through the serial
port. If it is not, the attenuation level is set through the parallel port. A separate user-
furnished System Controller is assumed to be the source of the M&C capability when
operating the HPA.