1. Introduction
The Radtel RT-4D is a versatile dual-mode digital DMR and analog two-way radio, designed for reliable communication across various frequency bands. It supports dual time slot operation (Tier 1+2) and offers a wide range of features for both amateur and professional users. This manual provides detailed instructions for setting up, operating, and maintaining your RT-4D radio.
2. Package Contents
Before you begin, please check the package contents to ensure all items are present:
- Radtel RT-4D Radio Unit
- Antenna
- Battery
- Belt Clip
- Adapter
- Type-C Charger Cable
- Desktop Charger Cradle
- User Manual (PDF reference: User manual (PDF))
3. Product Overview
3.1. Buttons & Knobs
- Antenna: For transmitting and receiving signals.
- PTT Key: Push-To-Talk button for transmitting.
- Side Key 1 & 2: Programmable function keys.
- Battery: Power source for the radio.
- Power on/Volume Knob: Turns the radio on/off and adjusts volume.
- LED Indicator: Shows radio status (e.g., transmitting, receiving).
- LCD: Liquid Crystal Display for information.
- Mic: Microphone for voice input.
- Speaker: For audio output.
- Keypad: For inputting frequencies, channel numbers, and menu navigation.
- Ear/Mic/Programming Port: For connecting accessories or programming cable.
- Type-C Port: For charging.
3.2. LCD Display Icons
- VFO MODE/CH MODE/Zone-XXX mode: Indicates the current working zone.
- Main Working Band: Displays the primary operating band.
- D-XXXX / A-XXXX: Digital channel (D) or Analog channel (A) with channel number.
- T1/T2: Digital channel time slot; AM/FM modulation in analog channel.
- CXX: Digital channel color code; CTC/DCS is analog channel subtone; ENC is analog channel encrypted subtone; MUT is analog channel decoded subtone.
- H/L Power: H for high power, L for low power.
- W/N Band: W for wide band, N for narrow band.
- Sub Channel Information: Details about the secondary channel.
- Main Channel Information: Details about the primary channel.
- HD: Digital call hold status.
- System Time: Current time.
- Battery Level: Indicates remaining battery charge.
- Alert Voice: Icon for alert sound status.
- Dual Frequency Standby: Indicates dual watch mode.
- Unread SMS: Icon for new messages.
- Scanning: Indicates scanning is active.
- R/T: R for Reverse Frequency, T for Talk Around.
- Keypad Locked: Indicates keypad is locked.
- Signal Icon: Displays signal strength.
4. Setup
4.1. Battery Installation
To install the battery:
- Align the battery with the battery compartment on the back of the radio.
- Slide the battery into place until it clicks securely.
4.2. Antenna Attachment
To attach the antenna:
- Screw the antenna clockwise into the connector on the top of the radio until it is finger-tight. Do not overtighten.
4.3. Charging the Battery
The RT-4D can be charged using either the Type-C cable directly or the desktop charger cradle.
- Using Type-C Cable: Connect the Type-C cable to the radio's Type-C port and a compatible USB power adapter.
- Using Desktop Charger: Place the radio (with battery installed) into the desktop charger cradle. Ensure the charging contacts align. Connect the desktop charger to a power source.
5. Operating Instructions
5.1. Power On/Off
Rotate the Power on/Volume knob clockwise to turn the radio ON. Rotate counter-clockwise until it clicks to turn the radio OFF.
5.2. Keypad Functions
The keypad allows for various inputs and function access:
| Key/Icon | Function |
|---|---|
| PTT | Transmit the RF signal or exit the current operation interface. |
| Side key 1 | Define as PTT function (customizable long-press and short-press functions). |
| Side key 2 | Customize long-press and short-press functions. |
| Menu / Confirm / DTMF: A | Access menu, confirm selection, or DTMF 'A'. |
| Analog mode: DTMF input mode or DTMF: B | Switch to DTMF input mode in analog, or DTMF 'B'. |
| Cancel / Exit Menu | Cancel current operation or exit menu. |
| Switch A/B channel | Toggle between A and B channels. |
| DTMF or Dial-call mode: Deleted characters | Delete characters in DTMF or Dial-call mode. |
| Up Arrow | Adjust Up frequencies, channels or menus. DTMF: C. |
| Down Arrow | Adjust Down frequencies, channels or menus. DTMF: D. |
| 0 | Long press for defined function or DTMF code: 0. |
| 1 | Short press: number 0 or blank. Long press: defined function. DTMF code: 1. Text input: number 1/Chinese or English characters. |
| 2-9 | Short press: number 2-9. Long press: defined function. DTMF code: 2-9. Text input: number 2-9/Chinese or English characters. |
| * | Short press: switch channel number/channel+frequency/channel name. Long press: lock keypad. DTMF code: *. |
| # | Long press: switch channel mode/frequency mode/zone mode. DTMF code: #. Text input: Turn text input on or off, switch text input methods. |
5.3. Basic Settings (Menu 01)
Access the menu and navigate to 'Basic Set' to configure general radio parameters:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 Radio Name | Edit name | Set radio name or callsign. Press * to delete input, press # to select input method. |
| 02 Voice Prompt | On/off | Turn on/off voice prompt. |
| 03 Key Beep | On/off | Turn on/off keypad beep. |
| 04 Lock Timer | Off, 5s-600s | The time to lock keypad. |
| 05 Backlight | On/off | Turn on/off display backlight. |
| 06 Light Timer | Off, 5s-600s | The time to Turn off the backlight. |
| 07 Brightness | 0-4 level | Choose the brightness level of the background light. |
| 08 Menu Exit | Off, 5s-600s | The time to exit menu. |
| 09 State Timer | Off, 5s-600s | Show voltage, time, date. |
| 10 Dual Standby | On/off | Select dual standby or single standby. |
| 11 TX priority | Edit / Busy | Always transmit at main band / Switch to busy channel as the main band. |
| 12 Freq Step | 0.25,1.25,2.5,5, 6.25,10,12.5,20, 25,50,100,500, 1M,5M | Set the frequency or scan step. |
| 13 Talk Around | Off, Talk Around, Invert Freq | Set repeater mode or normal mode. |
| 14 Save Mode | Off, 1:1-1:3 | Set the power saving ratio, dual frequency standby mode without entering power-saving mode. |
| 15 Scan Mode | CO, TO, SE | CO: Stops scanning until signal disappears. TO: Stops for preset time, then resumes. SE: Exits scan and remains on frequency. |
| 16 Scan Direction | UP, DOWN | Set the scanning direction. |
| 17 Scan Dwell | 0-30 | Set the scan stop time for TO scan mode. |
| 18 Scan Return | Original CH, Current CH | Set the current channel after scanning. |
| 19 Alarm Type | Local, Remote, Local+Remote | Radio emits alarm sound (Local), other radios receive alarm tone (Remote), or both (Local+Remote). |
| 20 Main PTT TX | Area A | Transmit in main area or always transmit. |
| 21 Area A Mode | CH mode, Zone mode, Freq mode | Set the Channel mode, Frequency mode or zone mode in A area. |
| 22 Area A Show | Show CH No., Show Freq, Show Alias | Set the display way in the selected mode. |
| 23 Area A Zone | Zone1-Zone256 | Set the zone numbers. |
| 24 Area B Mode | CH mode, Zone mode, Freq mode | Set the Channel mode, Frequency mode or zone mode. |
| 25 Area B Show | Show CH No., Show Freq, Show Alias | Set the display way in the selected mode. |
| 26 Area B Zone | Zone1-Zone256 | Set the zone numbers. |
| 27 Save CH | CH-0001-CH-1024 | Save the frequency and tone into channels. |
| 28 Delete CH | CH-0001-CH-1024 | Delete the frequency and tone in this channel. |
| 29 Instruction | barcode | Scan barcode to get user manual. |
| 30 Version | Version info. | Show the version information. |
| 31 LCD Contrast | Display contrast | Display contrast, the higher the value, the deeper the contrast. After setting, a restart is required. |
| 32 Initialization | Cancel / Ensure | Confirm or cancel the initialization. |
5.4. Key Define (Menu 02)
Customize the functions of Side Key 1, Side Key 2, and numeric keys for short and long presses:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 Slaver PTT | On, off | Set the side key 1 as the PTT button. |
| 02 Side key 1 S | None, Monitor(Ana), H/L Power, Dual standby, Tx priority, Scanning, Backlight on/off, Roger beep, FM radio, Talkaround, Alarm, Freq Detect, CTC/DCS scan, Single tone, Status query, Remote Monit, Color code scan, Remote Stun, Remote kill, Rmt Wake up, Online check, LCD brightness, Noaa mode | Set the short press function for Side Key 1. |
| 03 Side key 1 L | Same as 02 Side key 1 S options | Set the long press function for Side Key 1. |
| 04 Side key 2 S | Same as 02 Side key 1 S options | Set the short press function for Side Key 2. |
| 05 Side key 2 L | Same as 02 Side key 1 S options | Set the long press function for Side Key 2. |
| 06 0 Press Long | Same as 02 Side key 1 S options | Set the long press function for the '0' key. |
| 07 1 Press Long | Same as 02 Side key 1 S options | Set the long press function for the '1' key. |
| ... | ... | ... (Similar options for keys 2-9, *, #) |
5.5. Analog Set (Menu 03)
Configure settings specific to analog mode operation:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 SQ level | 0-10 | Setting the squelch level. Lower levels are more susceptible to interference, higher levels reduce sensitivity. A middle setting is generally recommended. |
| 02 TX Start Tone | On, off | The tone before transmitting. |
| 03 TX End Tone | Off, roger beep1, roger beep2, Radio name | The tone at the end of transmission or when sending radio name. |
| 04 Single Tone | 1750Hz | Edit the tone frequency in Key Define. |
| 05 Mic Gain | 0-31 | Adjusts the microphone sensitivity; higher value means higher sensitivity. |
| 06 SPK Gain | 0-63 | Adjusts the speaker volume; higher value means higher volume. |
| 07 Detect Range | Frequency range | Set the frequency range to detect frequency from other radios. |
| 08 Repeater Delay | 0-2000ms | Set the repeater delay time. |
| 09 DTMF Delay | 0-2000ms | Set DTMF delay time. |
| 10 DTMF Interval | 30-200ms | Set DTMF Interval time. |
| 11 DTMF Duration | 30-200ms | Set DTMF Duration Time. |
| 12 DTMF Mode | Off, Tx start, Tx end, Both | Set transmit the DTMF code. |
| 13 DTMF Select | 01-16 | Select DTMF code 1-16. |
| 14 DTMF Display | On,off | Turn on/off display DTMF decode. |
| 15 DTMF TX Gain | 0-127 | Set DTMF Transmit Gain. |
| 16 DTMF RX TH | 0-127 | Set DTMF Receive threshold. |
| 17 DTMF Control | On, off | Turn on/off DTMF control. |
| 18 Time Calibrate | On, off | Remote Time Calibrate. |
5.6. Digital Set (Menu 04)
Configure settings specific to digital mode operation:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 Personal ID | 00000001 | Digital ID from 1-16776415. |
| 02 Call Tone | On/off | Turn on/off call tone. |
| 03 Call End Tone | On/off | Turn on/off call end tone. |
| 04 Group Hold | 0000 | Set group call holding time. |
| 05 Single Hold | 0000 | Set single call holding time. |
| 06 SQ level | 0-16 | Set digital squelch level. |
| 07 Mic Gain | 0-15 | Set Microphone Gain. |
| 08 SPK Gain | 0-15 | Set speaker gain. |
| 09 Contacts Set | Contact list, add contract | Used to add/delete/change the contact information of the phone. There is one and only one All Call contact and it cannot be changed or deleted. Contact ID can be set range:1-16776415. |
| 10 Group List Set | Group list set | Used to add/delete/change the receiver group list information of the unit, when editing the members of the group call list, use the <icon> key to select the members of the group call contact, the background of the selected member turns black, the <icon> key to deselect. |
| 11 Encryption Set | Key 1-256 | [Encryption Key Setting] is used to change the DMR voice encryption information of this unit. |
5.7. Channel Set (Menu 05)
Manage channel-specific parameters:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 CTC/DCS | Set TX/RX CTCSS/DCS | Press * to switch them. |
| 02 RX CTC/DCS | RX CTCSS/DCS | Press * to switch them. |
| 03 TX CTC/DCS | TX CTCSS/DCS | Press * to switch them. |
| 04 DCS Encrypt | Standard, mute code, encrypt1-3 | Encrypt1-3 use to encrypt for standard DCS. Mute code to set the current channel as subtone. |
| 05 Mute Code 1 | Non-standard sub-tones | Non-standard sub-tones of other radios as measured by the one-touch frequency measurement function. |
| 06 Mute Code 2 | ||
| 07 Mute Code 3 | ||
| 08 Band Width | Wide, narrow | Set the channel bandwidth. |
| 09 Tail Tone | On/off | Turn on/off tail tone. |
| 10 Scrambler | Off, 1-8 | Set 1-8 groups of scrambler. |
| 11 Busy Lock | Off, carrier, ctc | Busy channel lockout. |
| 12 TX Power | High, low | Set high/low output power. |
| 13 Scan Add | Add, remove | Add or remove to scan lists. |
| 14 TOT | Off, 5s-600s | Set the time out timer. |
| 15 CH Alias | Channel name | Edit the channel name. |
| 16 Offset Dir | +/-/0 | Set offset direction. |
| 17 Offset Freq | Offset freq | Set offset frequency. |
5.8. Zone Set (Menu 06)
The radio supports 256 zones. You can edit each zone name and its associated channels. There are 1024 channels in total across all zones.
5.9. Message (Menu 07)
Manage text messages on your radio:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 New SMS | Edit message | Edit SMS message. |
| 02 Inbox | Store SMS | Store SMS. |
| 03 Outbox | Send SMS | Send SMS. |
| 04 Drafts | Edit SMS draft | Edit SMS draft. |
| 05 Default SMS | Preset SMS | Preset SMS. |
| 06 Clear All SMS | Delete all SMS | Delete all SMS. |
5.10. FM Radio (Menu 08)
Access and manage the built-in FM radio function:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 Work Mode | CH mode, frequency | Set working mode. |
| 02 RX Standby | On/off | Turn off radio when RX mode. |
| 03 Scan Mode | One station, all range | Set the search mode. |
| 04 Area | FM radio zone | Set 16 channels in each zone. |
| 05 Channel | FM radio channels | Set 16 FM radio channels. |
5.11. Time Manage (Menu 09)
Configure time-related settings and schedules:
| Menu | Sub Menu | Function |
|---|---|---|
| 01 APO | On, off | Set auto power on/off. |
| 02 APO Timer | Power off timer | Set power off timer. |
| 03 System Time | System time | Adjust system time. |
| 04 Clock 1 Type | Off, once, every day | Set clock 1 type. |
| 05 Clock 1 Timer | Clock 1 timer | Set clock 1 timer. |
| 06 Clock 2 Type | Off, once, every day | Set clock 2 type. |
| 07 Clock 2 Timer | Clock 2 timer | Set clock 2 timer. |
| 08 Clock 3 Type | Off, once, every day | Set clock 3 type. |
| 09 Clock 3 Timer | Clock 3 timer | Set clock 3 timer. |
| 10 Clock 4 Type | Off, once, every day | Set clock 4 type. |
| 11 Clock 4 Timer | Clock 4 timer | Set clock 4 timer. |
| 12 Schedule | List 1-128 | Set the schedule. |
5.12. Advanced Functions
- Frequency Input: Press # to enter VFO (Frequency) mode. Input the desired frequency value using the numeric keypad (8 digits) to complete the operation.
- Repeater Frequency Input: Go to the Channel Setting menu to configure different directions and frequencies for repeater use.
- DMR Voice Encryption: The RT-4D offers three encryption methods: ARC, AES128, and AES256. For two devices with voice encryption to communicate, they must have the same encryption type, the same serial number of the encryption key, and the same key value.
- Dialing Call: In digital channel mode, press the 'Menu' key to enter the dial interface. Use the arrow keys to switch call types. Input the call ID via the keypad and press PTT to send the call.
6. Specifications
| Feature | Specification |
|---|---|
| Model Number | RT-4D |
| Brand Name | Radtel |
| Walkie Talkie Type | Portable |
| Material | Plastic |
| Frequency Range (Analog RX) | 108-136MHz AM, 174-350MHz, 470-620MHz |
| Frequency Range (Analog TX/RX) | 136-174MHz, 350-470MHz |
| Frequency Range (Digital TX/RX) | 136-174MHz, 400-470MHz |
| Output Power (W) | 3W-5W |
| Battery Capacity (mAh) | 3500mAh |
| Storage Channel | 1024 Channels (+2 VFO) |
| Channel Spacing | 25KHz/12.5KHz |
| Working Voltage | 7.4V DC |
| TX Power | 5W |
| Charging Method | Type-C Cable/Desk-top Charging (Optional) |
| Dimensions (Without Antenna) | 112*61*38mm |
| Weight | 198g |
| Waterproof / Water-Resistant | No (Dust-proof, NOAA) |
| Is_Display | Yes |
| Maximum Range | 3km-5km |
| Certification | CE, FCC |
7. Maintenance
- Cleaning: Use a soft, damp cloth to clean the radio's exterior. Do not use harsh chemicals or solvents.
- Battery Care: To prolong battery life, avoid overcharging and fully discharging the battery frequently. Store the radio and battery in a cool, dry place when not in use.
- Antenna Care: Ensure the antenna is securely attached. Do not bend or force the antenna, as this can damage the connector.
- Water and Dust Protection: While the RT-4D is dust-proof and NOAA-rated, it is not fully waterproof. Avoid submerging the radio in water. Ensure all port covers are securely closed to prevent dust and moisture ingress.
8. Troubleshooting
If you encounter issues with your Radtel RT-4D, refer to the following common problems and solutions:
- Radio does not power on: Check if the battery is properly installed and charged. Ensure the power/volume knob is rotated clockwise.
- No audio from speaker: Check the volume level. Ensure no external earpiece/microphone is connected if you expect audio from the internal speaker.
- Cannot transmit or receive: Verify that the antenna is securely attached. Check the frequency and channel settings. Ensure you are in the correct mode (Analog/Digital). Confirm that the battery has sufficient charge.
- Keypad unresponsive: Check if the keypad lock is activated (long press '*' to toggle).
- Poor signal quality: Ensure the antenna is fully extended and unobstructed. Try moving to an open area. Check for local interference.
9. User Tips
- Programming: For advanced programming and customization, it is recommended to use the CPS (Customer Programming Software). Search online for 'Radtel RT-4D CPS download' to find the official software.
- Frequency Range: The radio supports a wide frequency range. Ensure you are operating within legal and licensed bands for your region.
- Mode Switching: Familiarize yourself with switching between Channel Mode, Frequency Mode, and Zone Mode using the keypad shortcuts for quick operation.
- Digital Features: Explore the digital settings for features like digital squelch, group calls, and voice encryption to enhance your communication security and clarity.
10. Warranty & Support
For warranty information and technical support, please refer to the official Radtel website or contact your authorized dealer. Keep your purchase receipt as proof of purchase for any warranty claims.