Lab599 Discovery TX-500, Руководство пользователя

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OVERVOLTAGE PROTECTION
When exceeding 15.0 volts, the transceiver won’t allow switching to TX mode, (the voltage
indicator on the display will become inverse) a significant excess (more than 16 volts) it can
cause the protective fuse to burn out, as well as the failure of the transceiver ! Use a power
source or battery with a voltage of 9 to 15 volts and a current of at least 2.5 Amps.
ATTENTION ! Exceeding the supply voltage above 15 volts can damage the
transceiver!
REVERSE POLARITY PROTECTION
If you connected a minus voltage source or battery instead of a plus, the transceiver will not
turn on. You must connect the external power supply correctly, please, see the pinout of the
power connector in the section "Controls end user interface”.
OVERHEAT PROTECTION
The transceiver has an internal protection against the overheating of the output stage of the
transmitter. If the TX continuous mode is too long, the output stage as well as the
transceiver body can be heated up. If the limit value is exceeded (about 60 degrees Celsius),
the transceiver won’t allow switching to TX mode. After the temperature drops, the TX
prohibition mode will turn off automatically.
ATTENTION ! During long-term TX mode (digital modes) do not block the air
access to the rear cover of the transceiver, or reduce the power.
TIP: Unfold both rear legs to increase the air flow convection.
HIGH SWR PROTECTION
If the impedance of the antenna is different than 50 ohms and there is no antenna tuner
connected, the SWR indicator on the display will show a value greater than 1.0. If the SWR
value is 3.0 or more (the SWR indicator on the display will be inverse), the transceiver will
automatically reduce the power output. If the value of SWR is greater than 3.0, then the
output power will decrease more.
ATTENTION ! Use a tuned antenna with a wave impedance of 50 ohms, this is
ideal (max output power), or use a matching device (automatic or manual tuner).
!
Protections
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