Hesambook
Full Member level 2
Without a doubt, FM transmitter and Receiver are among the top favorite electronic project topics, however, building a digital FM transmitter can be a challenging project for electronics enthusiasts. The transmitter can then be connected to a source of audio, such as a phone or computer, to broadcast music or other audio content.
In this project, I have introduced a compact stereo digital FM transmitter circuit that operates in the frequency range of 87MHz to 108MHz. The frequency can be adjusted using two tactile push-buttons, with a 0.1MHz step size. The heart of the circuit is an ATMega8 microcontroller, which communicates with a 0.96-inch SPI OLED display and the KT0803L FM transmitter chip via an I2C interface. You can directly connect a microphone or an AUX cable to the board to broadcast your desired sound, such as playing a piece of music from your cellphone, computer, … etc. After conducting some tests, it was found that the circuit operates quite stable, and the received sound is clear and sharp.
To design the schematic and PCB, I used Altium Designer 23 and shared the project with my friends to get their feedback and updates using Altium-365. The fast component search engine (Octopart) allowed me to quickly consider components’ information and also generate the BOM. To get high-quality fabricated boards, I sent the Gerber files to PCBWay. I am confident that utilizing this circuit will be an enjoyable and fulfilling experience for you.
References
Full Article + Schematic + PCB + Code: https://bit.ly/3nlPFTV
[1]: TLV1117-5.0: https://octopart.com/tlv1117-50cdcyr-texas+instruments-669252?r=sp
[2]: TLV1117-3.3: https://octopart.com/tlv1117-33idcyr-texas+instruments-669250?r=sp
[3]: MMBT304: https://octopart.com/mmbt3904lt1htsa1-infineon-21387159?r=sp
[4]: 2N7002: https://octopart.com/2n7002-7-f-diodes+inc.-335069?r=sp
[5]: KT0803L: http://radio-z.ucoz.lv/kt_0803/KT0803L_V1.3.pdf
[6]: ATmega8-AU: https://octopart.com/atmega8u2-au-microchip-77760652?r=sp
In this project, I have introduced a compact stereo digital FM transmitter circuit that operates in the frequency range of 87MHz to 108MHz. The frequency can be adjusted using two tactile push-buttons, with a 0.1MHz step size. The heart of the circuit is an ATMega8 microcontroller, which communicates with a 0.96-inch SPI OLED display and the KT0803L FM transmitter chip via an I2C interface. You can directly connect a microphone or an AUX cable to the board to broadcast your desired sound, such as playing a piece of music from your cellphone, computer, … etc. After conducting some tests, it was found that the circuit operates quite stable, and the received sound is clear and sharp.
To design the schematic and PCB, I used Altium Designer 23 and shared the project with my friends to get their feedback and updates using Altium-365. The fast component search engine (Octopart) allowed me to quickly consider components’ information and also generate the BOM. To get high-quality fabricated boards, I sent the Gerber files to PCBWay. I am confident that utilizing this circuit will be an enjoyable and fulfilling experience for you.
References
Full Article + Schematic + PCB + Code: https://bit.ly/3nlPFTV
[1]: TLV1117-5.0: https://octopart.com/tlv1117-50cdcyr-texas+instruments-669252?r=sp
[2]: TLV1117-3.3: https://octopart.com/tlv1117-33idcyr-texas+instruments-669250?r=sp
[3]: MMBT304: https://octopart.com/mmbt3904lt1htsa1-infineon-21387159?r=sp
[4]: 2N7002: https://octopart.com/2n7002-7-f-diodes+inc.-335069?r=sp
[5]: KT0803L: http://radio-z.ucoz.lv/kt_0803/KT0803L_V1.3.pdf
[6]: ATmega8-AU: https://octopart.com/atmega8u2-au-microchip-77760652?r=sp