Codan Radio Communications AMP-4-410 Manuale Utente
7
In the local control mode, the 3-turns potentiometer “PWR CTRL” is used to set the output power. The range
of regulation lays between more than 30 W (when the potentiometer is rotated completely clockwise) and less
than 20 W in the opposite direction (both numbers are valid for the nominal power supply voltage, greater than
13 V, and RF drive, greater than 6 W). The potentiometer will start clicking when the end of the range is met.
In the remote control mode, the output power depends on the voltage at pin Z22 of the DC connector (Vctrl).
This voltage may change from 0 to 9.5 V. When Vctrl < 1 V, the PA works as an attenuator, and not more than
0.2 W is available at its output. The minimum rated power (20 W) is reachable with Vctrl ~ 4 V; the maximum
rated power (more than 30 W) is reachable, when Vctrl = 6…7V.
The output power is also controlled by the load mismatching, overvoltage and overheating protection circuits.
In the case of the load mismatching the power is reduced proportionally to the VSWR value, starting from
VSWR > 2. In the case of overheating (when the temperature of the heatsink exceeds +85°C), the unit switches
to stand-by mode. When the power supply voltage exceeds 17 V, the output power falls to less than 0.2 W.
of regulation lays between more than 30 W (when the potentiometer is rotated completely clockwise) and less
than 20 W in the opposite direction (both numbers are valid for the nominal power supply voltage, greater than
13 V, and RF drive, greater than 6 W). The potentiometer will start clicking when the end of the range is met.
In the remote control mode, the output power depends on the voltage at pin Z22 of the DC connector (Vctrl).
This voltage may change from 0 to 9.5 V. When Vctrl < 1 V, the PA works as an attenuator, and not more than
0.2 W is available at its output. The minimum rated power (20 W) is reachable with Vctrl ~ 4 V; the maximum
rated power (more than 30 W) is reachable, when Vctrl = 6…7V.
The output power is also controlled by the load mismatching, overvoltage and overheating protection circuits.
In the case of the load mismatching the power is reduced proportionally to the VSWR value, starting from
VSWR > 2. In the case of overheating (when the temperature of the heatsink exceeds +85°C), the unit switches
to stand-by mode. When the power supply voltage exceeds 17 V, the output power falls to less than 0.2 W.
8.
Unit Status Monitoring.
There are two features of unit status monitoring: LED at the Front Panel and signals at pins of the DC
connector.
LED “TX” is on, when the output power is not less than 20W.
LED “G/F” (General Fault) is on when the power supply voltage exceeds 17 V (in active mode only), or if the
temperature of heatsink exceeds +85°C (in both active and stand-by modes).
LED “VSWR” is on, if the load VSWR is greater than 2:1.
A LOW level of voltage (less than 2 V) at the monitoring pins of DC connector gives details about the alarm:
-
at pin B24: The power supply voltage exceeds 17 V (appears in active mode only), or heatsink temperature
is greater than +85°C;
-
at pin B26: The output power is less than 20 W(appears in active mode only);
-
at pin Z26: The load VSWR is greater than 2:1.