User's Manual
⑥ DC Power Terminal
Connect the HL-450B to a regulated DC power supply or 12 V battery using the included
DC power cord.
The red cord is positive (+) and the black one is negative (-). 60 A min. (peak) capacity is
required.
Use the supplied cord of the accessories or the equivalent wire size to avoid the voltage
drop.
⑦ ALC Pot
This pot is used to adjust the ALC output level. When it is gradually turned
counterclockwise, a negative DC voltage is obtained and the RF output is decreased.
Adjust the pot so that the drive power stays within 50 W max, and/or the desired output
power level is achieved.
(This ALC pot works when the ⑧ALC terminal is connected to the external ALC input
terminal of the radio.)
In the case of 400 W output, the DC voltage up to -10 V max. is produced as the ALC
voltage.
(Refer to (6) at page 7.)
⑧ ALC (Phono Jack)
Connect one end of the supplied ALC cable to ⑧ALC jack and the other end to the (Ext)
ALC jack of the radio. ALC helps suppress the over-drive to keep the amplified output
level at the desired level.
(a. Effective external ALC voltage differs from radio to radio. Usually -4 V to -6 V.
(b. If the radio is 50 W max model, or if the radio is worked modestly not to exceed 50
W output level, this ALC connection is not necessarily required.)