This page describes hardware and software design for digital USB FM transmitter, called FmStick. This hardware does not contain analogue parts (except RF part). The main idea – is to create transmitter, that looks like usb flash stick. This idea is not new, You can see some of this designs in market, like Griffi RocketFM or Keene USB FM Transmitter, both avaliable on Amazon. But device, described below – is different. It does not have analogue sound parts at all, and it supports RDS, and it is powerful.
The main features of this device are:
- Transmit Frequency: 76 … 108 Mhz
- Transmit Power: -60 … 20 dBm
- Audio Compression: Yes
- Audio Limitation: Yes
- Audio Signal Measurements: Yes
- Pre-Emphasis: 0/50/75 uS
- RDS: Yes
- RDS RadioText: Yes
- RDS Time: Yes
- Drivers Installation Needed: No
- Software Needed: No
- LEDs That shows state: Yes
- External power needed: No
FmStick Digital USB FM Transmitter - [Link]
This project is a FM tuner with a Phillips FM1216ME_MK3 tuner module and 6H30 tube output buffer. The device is controlled by 18F452 PIC microcontroller and also has a RDS decoder with a TDA7330B and a 16F84A PIC.
FM tuner with Phillips FM1216ME_MK3 module - [Link]
This project is a stereo FM transmitter with RDS. The transmitter frequency is controlled by a Philips TSA5511 PLL IC through I2C communication. For the RDS part the author used a programmed RDS IC’s, the MRDS192.
Test stereo FM transmitter with RDS - [Link]
This project is a high quality PLL FM transmitter with output power of 5 W. The transmitter includes RDS/SCA input and Audio/MPX input with optional pre-emphasis. It can be used with or without stereo encoder. Tuning over the FM band is provided by two buttons that control dual-speed PLL. The transmitter can work also without the LCD display.
5W PLL FM Transmitter – [Link]
This project used to display and report the main roads traffic status and incident. Here are some features :Dual display: colour road map (left) and detailed text messages (right) both with LED backlight,Up to 120 TMC messages are stored in memory,Auto/manual TMC message scrolling,GPS position locator/follower optional,Map navigation with mouse sensor and/or micro joystick,Map zoom 10km to 80km (in 10km steps) City and area presets preconfigured,High quality NXP TEF6901AH chip used for best performance,Integrated RDS/RBDS radio data demodulator. [via]
Traffic Message Channel receiver – [Link]
This decoder is fed by a RDS demodulator IC (or tuner) which has RDDA (data signal) and RDCL (clock signal) outputs.The microcontrolller is an Atmega168 clocked on the external 4.332MHz crystal from the RDS demodulator. TDA7330B RDS demodulator IC from STMicroelectronics to be used in this project. The TDA7330B is connected to the Atmega168 with RDDA connected to PD4 (on PORTD) and RDCL to INT0 (PD2). [via]
Atmega168 RDS decoder - [Link]
This project supports both RDS (Europe) and RBDS (USA) Tuner FM band 88..108 MhZ (Europe and USA.) The schematic consists of two major subcircuits:
- The actual RDS/RBDS Decoder(TDA7330) with the PIC18F452 and the 4×20 LCD display
- The FM Stereo tuner with headphone amplifier.
You can choose between a 4×20 character LCD or a smaller graphical LCD to display data. A simple RS232 interface can also be used.
RDS/RBDS decoder - [Link]