Furuno LH-3000 - Manual (Page 17)

2. OPERATION
11
2.3 Adjusting Key Backlighting
You may adjust the intensity of the key backlighting cyclically with the [DIM] key, in five
levels, including off.
2.4 Adjusting Output Level
Turn the [HAIL VOL] control to adjust the output volume from the horn speakers or intercom
speakers. Clockwise rotation increases volume; counterclockwise rotation decreases it.
2.5 Adjusting Listening Volume
Turn the [LISTEN VOL] control to adjust the listening volume from the Loud Hailer’s internal
speaker and external speaker (if connected).
2.6 Calling All Intercom Stations
1. In the standby mode, hold the microphone 2-3 cm from your mouth and press the PTT
switch on the microphone. Speak into the microphone. All intercom stations and both
horn speakers will hear you.
2. After speaking, release the PTT switch to return the equipment to the standby mode.
Note: To call all intercom stations while sounding warning signals, see page 17.