Instruction Manual

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( 8 ) PROTECTION
1) Over-drive Protection
When the RF driving power from the radio exceeds 5W, this amplifier will be in the
through mode (bypass).
WARNG LED lamp on the front panel will light.
2) Over-voltage Protection
When the supplied DC voltage exceeds 16V, this amplifier will become “bypass”
state and WARNG LED will light.
3) Reset
To reset, push the POWER switch twice after checking the possible cause of
protection shutdown.
(First push to turn POWER off, second push to turn POWER on newly.)
( 9 ) CAUTIONS and SOME ADVICE
1) The heat sink temperature may gradually become very high, as you keep
transmitting. Do not put anything on top of the heat sink, or ventilation will be
degraded. Also do not place the power amplifier under direct solar rays.
2) Refrain from operating with high SWR antenna, such as 2.0 or over. Tune the
antenna well for lower SWR (ideally 1.5 or lower). Manual or auto antenna
tuner may help achieve low SWR conditions. Antenna system must solidly be
connected through good 50 ohm coaxial cable and connectors with IN/OUT
terminals of HL-45B.
3) Do not exceed the RF input limit of 5W.
4) Rated DC power supply voltage is 13.8V. Higher voltage will give stress to the
expensive RF power MOS FETs. Never apply AC100V, DC24V, etc. or HL-45B
will be seriously damaged at once.
5) There is a case when DC output voltage of regulated DC power supply swings
up due to RF intrusion to internal control circuit of power supply. Choose the
stable power supply for RF stray having current capacity of more than 10A.