The terminal has much mosaic and discontinuous audio in the satellite networking that is made of 8620MCU, 8020 terminal and the satellite of a foreign country.
1,We examined the 8020 terminal and it was OK.
2,We test the PIN24 port on V35 board of MCU, found the clock signal level was only about 1V, the clock signal ST and RT was out of sync. This signal couldn’t be RS449 signal, because the RS449 signal level is about 5V. The V35 signal level is about 3V. We guided the customs to examine the settings of the satellite device and alter the signal port to RS449, the fault was settled.
Wrong settings of the satellite port.