Barrett PRC-4090 - Page 224

Analog to Digital Converter
This test checks if the A/D converter for measuring the nal stage voltage is
accessible. A failed test indicates an issue with the I2C bus on the microboard,
the pre amplier board, a loose connector between the two transceiver
halves or a defective A/D converter.
Temperature Sensor
This test checks if the temperature sensor for measuring the nal stage tem-
perature is accessible. A failed test indicates an issue with the I2C bus on the
microboard, the pre amplier board, a loose connector between the two
transceiver halves or a defective temperature sensor.
Digital to Analog Converter
This test checks if the D/A converter for controlling the boost converter is acces-
sible. A failed test indicates an issue with the I2C bus on the microboard, the
pre amplier board, a loose connector between the two transceiver halves
or a defective D/A converter.
Rx Current
This test checks if the overall current draw while in receive mode (idle) is below
1A. This test can fail if too many accessories (Dual Antenna Switch Unit, ATU,
linear amplier etc) are connected to the SDR or if the accessories are faulty.
Disconnect all accessories and rerun the tests. If the test is failed again, there is
an issue with the pre amplier board.
Tx Current
This test checks if the overall current draw while in transmit mode (BIAS current
added) is between 1A and 4A. A failed test indicates the same issues as with
the “Rx Current” test. Additionally, there may be an issue with the nal stage
on the pre amplier board.
Final Voltage
This test checks if the voltage of the nal stage is between 28V and 32V. A failed
test indicates a defective pre amplier board (port expander fails to cong-
ure the pre amplier board, the D/A converter fails to set voltage, the boost
converter fails or the A/D converter fails to read the voltage).
212
BARRETT PRC-4090 TACTICAL HF SDR TRANSCEIVER - APPENDICES