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Procyon – 80 MHz ARM Cortex M3 with SDRAM Ethernet SD USB

Procyon is a general purpose development board with special features for Ethernet, USB, and audio applications. It is based on Luminary Micro/Texas Instruments LM3S9x9x series of parts. The initial MCU is LM3S9B90. The board contains the following features: 80 MHz, 100 Pin Cortex M3 Processor 16 MB SDRAM accessed on a 50 MHz EPI bus USB Host/Device/OTG port microSD card slot (Attached to SSI1/SPI1) 10/100 Ethernet I2S header for DAC output interface Up to 24 GPIOs available 3 UART, 2 I2C, 1 CAN, 2 SPI/SSI (one shared with microSD card) 10-bit ADCs General purpose timers: four 32-bit or eight 16-bit FTDI/Basic UART debug/program interface, on 16 pin GPIO/configuration header Three 10 pin headers for daughter boards 20 Pin JTAG Header User LED and User switch [ ]

3 Transistor Audio Amp 80 milliwatt

This circuit is similar to the one above but uses positive feedback to get a little more amplitude to the speaker. I copied it from a small 5 transistor radio that uses a 25 ohm speaker. In the circuit above, the load resistor for the driver transistor is tied directly to the + supply. This has a disadvantage in that as the output moves positive, the drop across the 470 ohm resistor decreases which reduces the base current to the top NPN transistor. Thus the output cannot move all the way to the + supply because there wouldn't be any voltage across the 470 resistor and no base current to the NPN transistor. Circuit diagram : 3 Transistor Audio Amp Circuit Diagram This circuit corrects the problem somewhat and allows a larger voltage swing and probably more output power, but I don't know how much without doing a lot of testing. The output still won't move more than a couple volts using small transistors since the peak current won't be more than 100mA or so into a 2...

80 MHz 108 MHz FM transmitter circuit

FM transmitter or often called fm transmitter uses 2 transistors in this article uses 2 transistors 2n2222. If the fm transmitter is in use voltage supply of 9 volt battery and use an antenna whose length is less than 12 inches, then this fm transmitter will be within FCC limits. Signals from the microphone in the fm transmitter is reinforced by Q1, Q2 with carrier frequency generator is determined by the C5 and L1. The frequency of the FM transmitter is in the range 80 MHz - 108 MHz. L1 can be made ​​with as many as 24 e-mail wire wrap and 6 wrap. The following is a picture series for the fm transmitter fm transmitter referred to in article 2 of this transistor. This fm transmitter antenna is connected to the mid point of the antenna length L1 and preferably between 8-12 inches. FM Transmitter is only used for experiment and learning materials are not to be used for day-to-day, because the use of FM transmitter frequency regulated and protected by law may be understandable.