Dilshan R Jayakody’s Web Log

TEA5767 is electronically tuned FM stereo radio receiver comes from NXP for low voltage applications. TEA5767 based radio modules are now common in the field and this project is based on Samsung TT-502 radio module . The main objective of this project is to design low-cost FM tuner based on this TT-502 / TEA5767 module and commonly available electronic components. In this receiver the main controller is ATmega8 MCU, except to that TDA2822 is used as AF power amplifier, PT2257 is used to control the volume. In this given design MCU, PT2257 and TEA5767 radio module are set to work with a 3.3V power source. The LD33V voltage regulator is used to obtain 3.3V from the supply voltage. To control the receiver, MCU provides five push buttons. Those can be used to control volume, perform an automatic scan and manual tuning. The final version of TEA5767 based FM radio receiver. The firmware of this receiver is developed using MikroC for AVR and it is available to download with proje...

Audio output transformers are heavily used in a vacuum tube and some (older) transistor base audio power amplifiers, but these days output transformer are quite hard to find and expensive item. For homebrew projects, the best option is to construct those transformers by ourselves and this script helps to calculate winding parameters for those transformers. This " AF output transformer calculator " script is written using Python and it works with most of the commonly available Python interpreters . The script is available to download at google drive under the terms of GNU General Public License version 3.0 . Homebrewed 25k: 4 output transformer Once supplied the input parameters this script provides a winding ratio, the number of turns required for primary and secondary winding and required copper wire gauges for both primary and secondary windings, etc. We construct several AF output transformers based on results of this script, which including transformers for M...