72MHz-108MHz DIY FM Clock Radio Kit with digital display from Banggood

Few things are more fun to experiment with than "old style" radios! Peeking inside a radio is one of top things that sparks the interest of many young people in electronics!

Recently, while shopping for some electronics, an interesting FM radio kit came to my attention. It's an DIY (user assembled) FM radio with digital display and alarm clock. But what draw my attention to this kit was the fact that this radio can be easily modded to work outside of the commercial FM band and it has a digital frequency readout module that can be used in multiple radio projects! The radio is based on the popular CD2003GP/GB FM/AM radio IC. The digital frequency display uses the SC3610D IC, a frequency and clock display driver capable of up-to 150Mhz frequency display. Since the radio comes in kit form, it is also an excellent project to practice component assembling and soldering. 

There are two kits of this same radio, type 1 and type 2. They are identical, the only difference is that type 1 comes with the digital display module pre-assembled, which I recommend. Both kits cost around 9 USD with free shipping from Banggood. The radio operates from two AA batteries (3V), which are not included in the kit. 

FM radio kit assembly:

Assembly of FM radio kit is straightforward and should take well under two hours. All the necessary components are provided together with a big paper schematic of the radio circuit and parts list, which is excellent. Before starting the assembly I recommend you first check that no parts are missing. The kit that I received came with a few extra passive components and screws, which is a nice touch.

Things you need:

To assemble the radio you will need a a low power soldering iron, 60/40 soldering wire, a wire cutter to trim the components leads after soldering and a small Philips screwdriver. Desoldering braid (wick) will also come handy if you need to desolder or remove excess solder from a joint.

Assembly steps:

1. Start by inspect the main PCB and clean it if necessary. 
2. Install the passive components on the board: resistors, capacitors, coils, etc. 
3. Solder them in place and cut excess lead wires. 
4. Install and solder the transistors and the two IC's. Be careful when soldering the IC's and transistors, since excessive heat can easily damage them! 
5. Solder the speaker, antenna and battery wires to the PCB. 
6. Place the metallic switch domes on the digital display board with some plastic tape and connect the digital display to the main board by soldering the wires. 
7. Attach the speaker to the plastic case. 
8. Place the plastic buttons and the two boards and insert the screws. 
9. Attach the antenna wire to the antenna rod. 
10. Solder the battery wires to the battery compartment.

Before inserting the batteries check if all components are in place and soldered properly. All solder joints should have a shiny finish!

That's it! Turn on the radio and try to tune to some FM radio station. 

I have made a video of the assembly process. Please take a look:

Tuning adjustment:

You may need to adjust the tuning capacitor to set the low and high FM band limits or to get the best reception quality. This is easily accomplished by tweaking two adjustment trimmers on the back of the tuning capacitor.

Improvements and Hacks:
The radio works reasonably well as it is, but you can make some improvements easily. You can even make the radio receive the Air Band (108-136Mhz). This is part of the fun of course.

Main components (datasheets):
CD2003GP FM/AM Radio IC datasheet
SC3610 Frequency and Clock Display Driver datasheet
TDA2822M Audio Amplifier IC Datasheet
 

Buy the kit and support MakerCorner!
I may get a small fee if you buy the kit through a link in MakerCorner. If you want to buy this kit and you found this post helpful, please support my work by clicking on this link to Banggood. Thank you!