1. Introduction
This instruction manual provides detailed guidance for assembling and operating your RDA5807 DIY FM Radio Electronic Kit. This kit is designed for electronics enthusiasts and hobbyists to learn about radio technology, practice soldering skills, and build a functional digital FM radio with an LCD display. The assembled radio features enhanced audio clarity, dynamic visual RGB spectrum indicators, broad frequency reception, and powerful sound output.
Figure 1: Front view of the assembled FM Radio Kit.
2. Safety Warnings
- Soldering Safety: Always use appropriate safety gear, including safety glasses, when soldering. Ensure good ventilation to avoid inhaling solder fumes. Use a stable soldering iron stand.
- Power Supply: Use only a DC power supply within the specified voltage range (4.5V-5.5V). Incorrect voltage can damage components.
- Component Handling: Some electronic components are sensitive to static electricity. Handle them carefully, preferably on an anti-static mat.
- Sharp Edges: The acrylic case parts may have sharp edges. Handle with care during assembly.
- Small Parts: This kit contains small parts and is not suitable for young children due to choking hazards.
3. Package Contents
Please verify that all components listed below are present in your kit before beginning assembly. Refer to Figure 2 for a visual representation of the kit components.
Figure 2: Overview of all kit components.
- Main PCB (Printed Circuit Board)
- LCD1602 Display Module
- RDA5807 FM Radio Module
- STC Microcontroller (pre-programmed)
- Speaker (5W, 4 ohms)
- Telescopic Antenna
- USB Power Cable
- Resistors (various values)
- Capacitors (electrolytic and ceramic, various values)
- LEDs (RGB spectrum indicators)
- Push Buttons (for control)
- IC Sockets (for microcontroller and other ICs)
- Header Pins and Jumper Wires
- Acrylic Case Parts
- Screws, Nuts, and Standoffs for assembly
4. Specifications
| Feature | Specification |
|---|---|
| Product Model | TJ-56-634 |
| Type | Module |
| Working Voltage | DC 4.5V ~ 5.5V |
| Output Impedance | 4 ohms |
| Output Power | 5W |
| Output Channel | Mono |
| Receiving Frequency | 87.0 MHz ~ 108.0 MHz |
| Frequency Accuracy | 0.1 MHz |
| Equivalent Noise | >=30dB |
| Product Dimensions (L x W x H) | 120mm x 60mm x 20mm (4.72in x 2.36in x 0.79in) |
| Shell Size | 90mm x 70mm x 55mm |
Note: Dimensions are approximate and may vary slightly after assembly.
Figure 3: Assembled radio with approximate dimensions.
5. Assembly Instructions
This kit requires soldering. Please ensure you have basic soldering tools (soldering iron, solder, desoldering wick/pump, safety glasses, ventilation) and skills before proceeding. Always refer to the PCB's silkscreen markings for component placement and orientation.
5.1. Component Identification
Before starting, identify all components by comparing them with the provided component list and the PCB silkscreen. Pay close attention to resistor color codes and capacitor values.
5.2. Soldering Order
It is generally recommended to solder components from smallest to largest, and from lowest profile to highest profile. This prevents larger components from obstructing access to smaller solder pads.
- Resistors: Solder all resistors onto the PCB. Ensure correct values are placed in their designated positions.
- Diodes: Solder diodes, paying close attention to their polarity (band on diode matches band on PCB silkscreen).
- Ceramic Capacitors: Solder the small, non-polarized ceramic capacitors.
- IC Sockets: Solder the IC sockets for the microcontroller and other integrated circuits. Ensure the notch on the socket aligns with the notch on the PCB silkscreen.
- LEDs: Solder the LEDs. LEDs are polarized; the longer leg (anode) typically goes into the square pad, or match the flat side of the LED to the silkscreen.
- Electrolytic Capacitors: Solder the larger electrolytic capacitors. These are polarized; the longer leg is positive (+), and the shorter leg (marked with a stripe) is negative (-). Match the negative stripe to the corresponding marking on the PCB.
- Push Buttons: Solder the control buttons.
- Header Pins: Solder any header pins required for connecting modules.
- RDA5807 Module: Solder the RDA5807 FM radio module.
- LCD1602 Display: Solder the LCD1602 display module to its designated header pins.
- Speaker: Connect the speaker wires to the designated pads on the PCB.
- Antenna Connector: Solder the telescopic antenna connector.
- Microcontroller (STC): Carefully insert the STC microcontroller into its socket, ensuring the notch on the chip aligns with the notch on the socket and PCB. Do not force it.
5.3. Case Assembly
Once all electronic components are soldered and verified, assemble the acrylic case using the provided screws, nuts, and standoffs. The case protects the circuitry and provides a finished look. Ensure the PCB is securely mounted and the LCD and buttons align with the case openings.
6. Operating Instructions
6.1. Powering On
Connect the provided USB power cable to the radio kit and a suitable 5V DC power source (e.g., a USB wall adapter, power bank, or computer USB port). The LCD display should light up, and the RGB spectrum indicators may flash.
6.2. Adjusting Frequency
Use the designated buttons (typically marked with '+' and '-') to adjust the FM frequency. The frequency range is 87.0 MHz to 108.0 MHz. Pressing the buttons will increment or decrement the frequency by 0.1 MHz.
6.3. Adjusting Volume
Use the volume control buttons (also typically marked with '+' and '-') to increase or decrease the audio output volume. The current volume level will be displayed on the LCD.
6.4. Antenna Usage
Extend the telescopic antenna fully for optimal signal reception. Adjust its position and orientation to improve reception quality for weaker stations.
6.5. LCD Display
The LCD1602 display shows important information such as the current FM frequency and volume level. The RGB spectrum indicator lights will dynamically respond to the audio output, providing a visual element to your listening experience.
Figure 4: Close-up of the LCD display and control buttons.
7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the acrylic case and display. Avoid using harsh chemicals or abrasive materials.
- Storage: Store the radio in a dry, dust-free environment when not in use.
- Antenna Care: Handle the telescopic antenna gently to prevent bending or breaking.
- Power Off: Disconnect the power supply when the radio is not in use for extended periods.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No power/display | Incorrect power supply, loose connection, soldering error. | Check power supply voltage (4.5V-5.5V). Verify USB cable connection. Inspect all solder joints for shorts or cold joints. Ensure microcontroller is correctly seated in its socket. |
| No sound | Speaker not connected, volume too low, soldering error on audio path. | Check speaker connections. Increase volume. Inspect solder joints around the speaker and amplifier circuit. |
| Poor reception/static | Antenna not extended, weak signal, interference, soldering error on antenna circuit. | Extend the telescopic antenna fully. Try adjusting antenna position. Move away from sources of electronic interference. Check antenna connection solder joint. |
| LCD display issues (blank/garbled) | Loose LCD connection, soldering error, incorrect LCD module insertion. | Ensure LCD module is securely connected to its header. Inspect solder joints for the LCD. Verify correct orientation if it was inserted into a socket. |
| Buttons not responding | Button soldering error, button stuck. | Inspect solder joints for the unresponsive buttons. Ensure buttons are not physically stuck. |
9. User Tips
- Double-Check Before Powering: After completing assembly, always perform a visual inspection of all solder joints for bridges, cold joints, or incorrect component placement before applying power.
- Start with Low Volume: When first powering on, keep the volume low to avoid sudden loud noises.
- Experiment with Antenna: FM reception can be highly dependent on antenna position. Don't hesitate to experiment with the antenna's angle and extension to find the best signal.
- Learning Opportunity: Take your time during assembly. This kit is an excellent opportunity to understand basic electronic circuits and soldering techniques.
10. Warranty and Support
For any questions regarding the assembly or operation of your RDA5807 DIY FM Radio Electronic Kit, please contact the seller or manufacturer for assistance. Ensure you provide your product model (TJ-56-634) and a clear description of the issue for efficient support.
