Specifications

2-4-1-2 Changing frequency using the main tuning dial

While in VFO mode, the active VFO frequency may be ‘tuned’ using the rotary main tuning

dial which is mounted on the right side of the front panel. You may rotate the dial ‘clockwise’

to increase frequency or turn ‘counterclockwise’ to decrease frequency.

2-4-1-3 Changing frequency using UP arrow key or DOWN arrow key

The UP arrow key and DOWN arrow key provide a convenient method of frequency change.

The speed at which the receiver steps up or down depends upon the STEP SIZE which is

default to AUTO. In AUTO the step size, receiver mode etc. is taken from the factory

pre-programmed band plan but may be overridden at any time.

Push the UP arrow key to tune the receiver upward in whichever step size is selected, use

the DOWN arrow key to tune the receiver downward in frequency.

2-5 Changing receive mode

Due to the necessities of signal bandwidth, channel occupancy and transmission efficiency,

different receive modes are used by various services. Specifications being not consistent

throughout the world, it is sometimes necessary to change receive mode in order to monitor

various transmissions.

For your convenience, receive mode and tuning step size have been pre-programmed into

the AR-ONE auto-mode band plan data at the factory to simplify operation of the receiver,

especially while you familiarize yourself with all functions. Should you wish, the defaults may

be manually overridden at anytime so that you may select an alternative receive mode and

tuning step on any frequency.

Amplitude Modulation – Used by broadcast services throughout the world on long wave,

medium wave and shortwave. AM is also used by VHF airband, UHF military airband and

some PMR (Private Mobile Radio) and utility services.

There are two common types of FM (Frequency Modulation), these are:

NFM – Narrow Band Frequency Modulation – this provides high quality communication for

relatively short distance operation. FM uses a greater frequency bandwidth than other

modes such as SSB, so is less efficient.

NFM is the most common mode used above 30 MHz with the exception of the airbands.

NFM is widely used on the VHF bands: VHF marine band, 2m amateur band, 70 cm

amateur band, PMR (Private Mobile Radio) and utilities.