Instruction manual

5 Operating the ARD25

5-1 Power LED

Once the ARD25 is switched on, the green LED will light indicating power is applied to the

ARD25.

5-2 Receiver settings

1. Set your receiver to the desired frequency.

2. If you intend to monitor analog NFM (Narrow FM) mode, set the squelch

threshold and adjust the volume control to 10 o’clock position.

5-3 Receive mode

(1) DIGITAL mode

As the input signal to the ARD25 is taken from the 10.7 MHz IF output (before the IF

filter) of your receiver, you can decode digital signals regardless of the receiver’s mode

setting.

(Note: If you are using the AR8600 receiver, you MUST set it to the WFM (Wide FM)

mode to activate the 10.7 MHz IF output. Otherwise, no digital signals can be

decoded.)

Once a digital signal is received, the front BUSY LED and the P-25 LED will light GREEN

and the recovered audio can be heard from the internal speaker.

If a signal is received and the front BUSY LED is lit RED, but no recovered audio is

heard from the internal speaker, the received digital signal may be encrypted. Also,

there must be adequate signal strength for the ARD25 to function properly.

(2) Analog mode

If the received signal is sent in the analog NFM (Narrow FM) mode, the front BUSY LED

will light, and you can hear audio from the internal speaker. You can also adjust the audio

level using the audio gain control of your receiver.

(Note: If you are using the AR8600 receiver, set it to the WFM (Wide FM) mode to

activate the 10.7 MHz IF output. However, you can recover analog NFM (Narrow FM)

signals from the internal speaker even when the external speaker cable is not

connected to the ARD25.)

5-4 Speaker output level

Rotate the AF GAIN knob to the desired speaker output level. If you wish to use your

external speaker, connect it to the SP OUT jack on the rear panel.

If you like to use headphones, plug in to the PHONES jack on the front panel.