Table of Contents Table of Contents Introduction ........................... 3 Features........................3 Manual overview ......................3 Getting Started ........................4 What's included ......................4 Parts of the radio ......................5 Operation ..........................8 Turning on the Power ....................8 Setting the Manual Squelch ..................8 Selecting a Channel.....................9 Transmitting .......................10 Call Function ......................10 Channel 88 ........................10...
Introduction Introduction Features • Designed and Engineered in Japan • Built for Rugged Australian Marine Conditions • 2 Year Warranty • Dual Speakers: One speaker is mounted at the front of the unit allowing better sound clarity and the second speaker is built into the microphone hand piece. •...
Getting Started Getting Started What's included A M T R A N S C E I V E R UM423 AM Radio DC Power Cable Accessory Cable Mounting Bracket and knobs Mounting Hardware Microphone Hanger and Spare Fuse 250V 3A...
Getting Started Parts of the radio Antenna Accessory Heat sink connector connector (SO238) ANTENNA 13.8V DC Power connector Rear panel connector functions Connector Connects to For details, see Antenna connector External AM antenna with Connecting the radio, a male PL259 (SO238) page 22.
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Getting Started VOLUME (power) knob MENU / (turn clockwise ENTER to increase BUTTON display volume) & CHANNEL UP buttons DOWN Microphone cord A M T R A N S C E I V E R VHF DSC TRANSCEIVER ANL / NB CALL / PA knob SQUELCH...
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Getting Started Button Press to... Press and hold to... ANL (Automatic Noise Limiter) on/ NB (Noise Blanker) on/off ANL / NB Call tone transmission PA mode on/off CALL / PA Start scanning the channels saved Save a channel into SCAN / MEM in memory.
Operation Operation Turning on the Power Turn the radio ON by rotating the Volume/ON/OFF control clockwise. AM TR A NS C EI V ER MENU ENTER DCS/CTCSS Setting the Manual Squelch Turn the SQUELCH control to adjust the Squelch. You must select a channel which is not in use before setting the SQUELCH control. (see page 9 for “Selecting a Channel”).
Operation Selecting a Channel Press keys on the handset A M T R A N S C E I V E R or base to select the desired channel. For your reference a list of the available channels, corresponding frequencies and guidelines for their use is printed on page 28.
Operation Transmitting The UM423 AM radio uses the Inshore Boating Radio Service Band channels. Select the desired channel. Press the microphone’s PTT button and speak normally into the microphone. Hold it approx. 7cm from your mouth. Release the PTT button to end the transmission and listen for a reply.
Operation Scanning The AM Marine Radio has a scanning feature that allows you to search for active channels A M T R A N SC EI VE R automatically. Furthermore, the AM Marine Radio is designed to have two types of scanning; Open Scanning (OS) and Group Scanning (GS), to give you flexibility and allow you to use the radio more...
Operation Open Scan (OS) Mode Allows continuous scanning of all selected channels. If an active channel is found, scanning will stop on that channel. If the received signal ceases, the unit will wait 3 seconds for the signal to return, otherwise scanning resumes. To skip the active channel, press any of the channel keys on the base or handset.
Operation Priority Channel To set the Priority channel. [MENU/ENTER] 1. Press two times. The current priority watch channel flashes. 2. Press any channel key on the base or handset to change the Priority Watch channel. [MENU/ENTER] 3. Press and hold to store the setting and exit from the menu mode.
Operation Busy Channel Lockout If the channel is already in use, A M TR AN SCEIVER you can prevent the AM Marine Radio from transmitting . [MENU/ENTER] 1. Press three times. The BCL setting flashes. 2. Press any channel key on the base or handset to change the setting between ON or OFF.
Operation Roger Beep [MENU/ENTER] 1. Press five times. A M T R A N S C EI V ER The roger beep setting flashes. 2. Press any channel key on the base or handset to change the setting between ON or OFF. [MENU/ENTER] 3.
Operation Beep On/Off 1. Press [MENU/ENTER] six times. The Beep setting flashes. A M T R A N SC EI VE R 2. Press any channel key on the base or handset change the setting between ON or OFF. 3. Press [MENU/ENTER] to store the setting.
Operation ANL (Automatic Noise Limiter) ANL will reduce harsh background noise A M T R A N SC E I VE R caused by some transmission interference. 1. Press [ANL/NB], the ANL icon appears. 2. Press [ANL/NB] to turn ANL off, the ANL icon disappears.
UM423 AM sounds the siren tone continuously. To cancel the single cycle or continuous siren; Press [SIREN] or PTT key. The UM423 AM stays in the PA mode. Pressing [88/DUAL] also cancels the siren and changes to CH88. The siren via PA speaker cannot be controlled.
Installing the Hardware Mounting the radio The UM423 AM can sit at any angle in the mounting bracket so it can easily accommodate the best location. First, determine the best place to mount the radio. For optimum performance, find a location that can: •...
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Installing the Hardware Position the radio into the desired location. Mark the edges of the bracket on the mounting surface. Remove the mounting bracket drill template from the back of the manual, and use the template to mark the drill holes on the mounting surface.
Installing the Hardware Connecting the radio To operate correctly, your UM423 AM requires two electrical connections: • providing it with power from the boat’s electrical system • connecting a HF-AM marine antenna to the antenna connector Power supply requirements AM antenna requirements Nominal 13.8 VDC power supply with...
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Install your antenna according to the manufacturer’s instructions. See Antenna Selection and Installation on page 29 for more details. Connect the PL-259 connector from the antenna lead-in wire to the SO238 connector labeled ANTENNA on the back of the UM423 AM. Radio connector, Antenna lead-in...
Installing the Hardware Connecting accessories Accessory connector Accessory cable Black: Ext. Speaker (-)/GND Red: External Speaker (+) Brown: PA Speaker (+) Blue: PA Speaker (-)/ GND Bare wire: Ground Orange: Not Used Green: Not Used Yellow: Not Used 13.8V DC Line up arrows to connect...
If you adjust the knob on VOLUME-PWR the radio, it will also adjust the external speaker volume. The UM423 AM supports an external speaker with the following specifications: • Minimum impedance of 4 Ohms •...
Connecting to an external PA Speaker If you connect the radio to a PA speaker, you can use the PA feature to make announcements to other boats and people nearby. The UM423 AM supports an external PA speaker with the following specifications: •...
Engine Noise Suppression Interference from the noise generated by the electrical systems of engines is sometimes a problem with radios. The UM423 AM has been designed to be essentially impervious to ignition noise and alternator noise. However, in some installations it may be necessary to take measures to further reduce the effect of noise interference.
Specifications Specifications Radio specifications (All specifications are subject to change without notice.) General Controls , Squelch OLUME Status Indicators Transmit power, Transmit, Busy, Siren, Scan mode, Dual Watch mode, Priority Channel, Noise Blanker, Automatic Noise Limiter, Roger Beep on, Key Beep on, Group Scan, Memory, Frequency and Channel Display Display LCD (ICON)
Antenna Selection and Installation Your UM423 AM has been designed to accommodate all of the popular marine HF- AM antennas. However, the selection and the proper installation of the antenna is the responsibility of the user or installer.
Please refer to our Uniden website for any details or warranty durations offered in addition to those contained below. Warrantor The warrantor is either Uniden Australia Pty Limited ABN 58 001 865 498 (“Uniden Aust”) or Uniden New Zealand Limited (“Uniden NZ”) as the case may be.