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Radio Soldering Kit

RADIOSOL

Introduction

This page contains complete, bilingual online instructions for building and operating the Radio Soldering Kit — a soldering project that turns a handful of through-hole components into a fully working FM radio with a digital tube display, station memory and adjustable volume.

Assembly video

Video 1 — Full soldering and assembly walkthrough (16:17).

Operating video

Video 2 — Settings and how to use the finished radio (05:27).

I. Functions

  1. When the radio has no stored stations, it automatically searches for nearby stations and stores them (up to 30 stations; any more than that cannot be saved).
  2. List management of stored radio stations.
  3. Adjustable radio volume.
  4. Adjustable search channel threshold.
  5. Radio signal strength can be viewed on screen.
  6. Includes a power-saving mode.

II. Characteristics

  1. The upgraded RDA5807 radio has more features and is easier to solder.
  2. Paired with the RDA5807 radio module, it offers noise cancellation, bass enhancement, high sensitivity, low noise and strong anti-interference capability.
  3. Equipped with a potentiometer offering 15 adjustable volume levels, so you can find the sound level that satisfies you.
  4. The digital tube display makes it easier to read the radio channel and signal strength.
  5. Includes power-off memory, automatic channel search and channel storage.
  6. Includes a power-saving mode that makes the radio more energy-efficient.
  7. Power supply: 3 AAA batteries or USB power (choose one).
  8. Receiving frequency band: 87–108 MHz.
  9. Maximum operating current: approximately 250 mA (with the volume set to maximum).
  10. PCB size: 95.5 x 59 mm.

III. Component List (BOM)

Verify the contents of your kit against the bill of materials below before starting.

Bill of materials table for the RDA5807 radio soldering kit

IV. Circuit Principle (Schematic)

Schematic diagram of the RDA5807 radio soldering kit

V. Component Map

Silkscreen component map of the radio soldering kit PCB, showing every reference designator

VI. Soldering Tutorial

Step 1 — AMS1117 and RDA5807 module. Solder the AMS1117 chip and the RDA5807 radio module.

Soldering the AMS1117 chip and the RDA5807 radio module

Step 2 — USB socket. Solder the USB socket.

Soldering the USB socket

Step 3 — Resistors. Solder the 510 Ω, 1K and 10K resistors. These are 5-band resistors — use the color code and PCB position table to identify and place each one.

Resistor color code reference:

ValueColor codePCB positions
10K Ω
  1. Brown
  2. Black
  3. Black
  4. Red
  5. Brown
R16
1K Ω
  1. Brown
  2. Black
  3. Black
  4. Brown
  5. Brown
R2, R3, R4, R5, R6
510 Ω
  1. Green
  2. Brown
  3. Black
  4. Black
  5. Brown
R7, R8, R9, R10, R11, R12, R13, R14
Soldering the 510 ohm, 1K and 10K resistors

Step 4 — 1uF electrolytic capacitor. Solder the 1uF electrolytic capacitor and bend its leads. (Long leg +, short leg −)

Soldering and bending the leads of the 1uF electrolytic capacitor

Step 5 — IC sockets. Solder the 8-pin and 16-pin IC sockets. (The notched side of each IC socket must match the notch printed on the silkscreen.)

Soldering the 8-pin and 16-pin IC sockets

Step 6 — Red LED. Solder the red LED. (Long leg +, short leg −)

Soldering the red LED, long leg positive

Step 7 — Toggle switch and audio jack. Solder the toggle switch and the audio jack.

Soldering the toggle switch and the audio jack

Step 8 — Ceramic capacitors. Solder the 104 ceramic capacitors.

Soldering the 104 ceramic capacitors

Step 9 — Potentiometer. Solder the 200K potentiometer.

Soldering the 200K potentiometer

Step 10 — 100uF electrolytic capacitors. Solder the 100uF electrolytic capacitors. (Long leg +, short leg −)

Soldering the 100uF electrolytic capacitors

Step 11 — Digital tube display. Solder the digital tube display. (Pay attention to its orientation.)

Soldering the digital tube display, respecting orientation

Step 12 — Push buttons. Solder the 6×6×12.5 mm push buttons.

Soldering the 6x6x12.5mm push buttons

Step 13 — Antenna. Secure the radio antenna with an M2 screw and nut, then solder it.

Securing and soldering the radio antenna with an M2 screw and nut

Step 14 — Insert the microcontroller and amplifier. Insert the STC8G1K17 and TDA2822 chips into their corresponding IC sockets. (The notched side of the chip must face the notched side of the socket.)

Inserting the STC8G1K17 and TDA2822 chips into their IC sockets

Step 15 — Battery contacts. Insert the battery contacts (spring terminals) into their corresponding positions on the case.

Inserting the battery spring contacts into the case

Step 16 — Wire the battery contact. Solder one end of the red/black wire to the short battery contact, and the other end to the circuit board. (Red +, Black −)

Soldering the red and black wire between the short battery contact and the PCB

Step 17 — Wire the speaker. Solder one end of the red/black wire to the speaker, and the other end to the circuit board. (Red +, Black −)

Soldering the red and black wire between the speaker and the PCB

Step 18 — Fit the speaker and close the case. Fit the speaker into its slot, close the case, and secure it with the self-tapping screws.

Fitting the speaker into its slot and closing the case with self-tapping screws

Step 19 — Batteries and battery cover. Install the batteries, close the battery cover, and secure it with a self-tapping screw.

Installing the batteries and securing the battery cover

Step 20 — Button caps. Install the button caps. Your radio is now complete.

Finished radio soldering kit with button caps installed

VII. Instructions for Use

1. Interface description

Attention: The USB port and the batteries cannot power the radio at the same time — choose one or the other, otherwise the radio may be damaged. Before closing the case, adjust the potentiometer to set the volume to a level you are satisfied with.

Diagram labeling the audio jack, power switch, USB port, volume potentiometer and V+/V-/F-/F+ buttons

2. Operating instructions

Main interface (with no settings changed, only the channel is shown by default)

FunctionDisplay / StatusOperationDescription
Increase volumeCurrent volumeShort or long press V+Range 0–15, default 8. The higher the number, the louder the volume; the lower, the quieter.
Decrease volumeCurrent volumeShort or long press V-Same range as above.
Previous stationCurrent frequencyShort press F-Switches between stored stations.
Next stationCurrent frequencyShort press F+Switches between stored stations.
Search down for a stationCurrent frequencyLong press F-Stations found this way are not automatically stored.
Search up for a stationCurrent frequencyLong press F+Stations found this way are not automatically stored.
Re-search all stationsCurrent frequencyLong press V+ and F+Automatically clears the stored stations, then searches for and stores new ones.
Enter setting modeMain interfaceLong press V+ and V-Sets the search threshold, power-saving mode and signal-strength display.
Enter channel management modeDigital tube flashesLong press F+ and F-Lets you add or delete your own stored stations.

Setting mode

FunctionOperationDescription
Radio threshold Short press V+ or V- to change the value, short press F+ or F- to save and move to the next setting Range 0–15, default 4. A higher value finds more stations (including weak or invalid ones); a lower value finds fewer stations (and fewer weak or invalid ones).
Power-saving mode Short press V+ or V- to turn on/off, short press F+ or F- to save and move to the next setting Range 0–1, default 0. 0 = off, 1 = on. In power-saving mode, about 13 seconds without any input automatically turns off the digital tube display.
Signal strength display Short press V+ or V- to turn on/off, short press F+ or F- to save and return to the main interface Range 0–1, default 0. 0 = off, 1 = on. When turned on, the main interface alternates between the frequency (e.g. example frequency reading 094.2 ) and the signal strength (e.g. example signal strength reading 020 ).

Channel management mode (the digital tube flashes while in this mode)

FunctionDisplay / StatusOperationDescription
Previous stationCurrent frequencyShort press F-Switches between stored stations.
Next stationCurrent frequencyShort press F+Switches between stored stations.
Search down for a stationCurrent frequencyLong press F-Stations found this way are not automatically stored.
Search up for a stationCurrent frequencyLong press F+Stations found this way are not automatically stored.
Increase frequencyCurrent frequencyShort press V+Manually tune to the desired channel; the new channel is not automatically stored.
Decrease frequencyCurrent frequencyShort press V-Manually tune to the desired channel; the new channel is not automatically stored.
Add channelCurrent channel indexLong press V+Adds the channel to the list; the frequency and the current channel index swap places (up to 30 stations can be stored).
Delete channelCurrent channel indexLong press V-Removes the channel from the list; the frequency and the current channel index swap places.
Exit and saveMain interfaceLong press F+ and F-Returns to the main interface.

Icon reference used above: threshold setting digital tube icon dP, radio threshold setting · power-saving setting digital tube icon Po, power saving setting · signal-strength setting digital tube icon Sn, signal strength setting.

If you do not have this kit or need extra parts to complete your project, you can order online. Check price and availability at the secure online store.

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Finished Radio Soldering Kit