User's Manual

SATELLINE-4Pro
User Guide v0.93 DRAFT
14
3 SATELLINE-4Pro SPECIAL FEATURES
3.1 Call Sign
SATELLINE-4Pro has a CALL SIGN identifier -feature required in some countries. A call sign can be
formally assigned by a government agency, informally adopted by individuals or organizations, or
even cryptographically encoded to disguise identity of a station.
A call sign is an FCC (in US) or other regulatory authority assigned identifier that is issued along
with the license for operating a radio modem. This field is for entering your call sign. The modem
automatically broadcasts the specified call sign periodically. If this field is empty, there is no call
sign information.
Call sign setup can be found in PROG-menu clause Radio settings and further in its sub clause Call
sign. Call sign has three (3) different setups. With Call Sign Mode you can set Morse code
transmission ON or OFF. Call Sign ID defines which Morse code will be transmitted. Only capital
letters and numbers are allowed. If the digits are wrong kind, there will be message: Value error.
Small letters will be converted to capital letters automatically. If Call Sign ID field remains empty,
the Call Sign transmission will not be activated. Call Sign Timer is the transmission delay of Morse
codes. Minimum and default transmission time is 15 minutes.
During Call sign transmission the CTS-line of the modem is not in active state. This is to inform
terminal equipment that the modem is not ready to neither receive data from serial port nor forward
it. The modem deletes all data (also SL commands), which has arrived to serial port during call sign
transmission. Call sign transmission lasts 1-4 seconds depending on the number of digits.
3.2 Temperature protection of RF power amplifier
RF power amplifier is protected against overheating. The power of transmitter is lowered step by
step if the inner temperature exceeds certain levels as shown below.
Temperature inside a modem Carrier power
Over 75°C 25 W
78°C 20 W
80°C 10 W
85°C 2 W
90°C 0 W (transmitter OFF)
When the ambient temperature is under 30°C and transmitter duty cycle does not exceed 40%,
the temperature inside the modem does not exceed the trigger level.
The internal temperature is measured in the beginning of every transmission and at once when
modem cools down. The carrier power increases with falling temperature so that at 85°C carrier