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Aether4E0A / IR-Transponder-ATTiny85

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Why not a single 2222a transistor? #1

Open EdwardDimaguila opened 8 years ago

EdwardDimaguila commented 8 years ago

is there any reason why you are using 2 transistors instead of 1 to drive the ir led?

Aether4E0A commented 8 years ago

For modulation, the 455KHz Carrier needs to be logically ANDed with the UART 38400 signal. The two transistors perform this function easily. At the time, I wanted to avoid software headaches. I almost went insane determining how to set the registers for Fast PWM on the ATTiny85.

One could modify this to use just one, by perhaps turning the Fast PWM on and off according to the UART 38400 signal. However, one must factor in delay times due to Fast PWM initialization. Read the ATTiny85 datasheet carefully to go further in depth.

Also, this uses MOSFETs, as these have a faster switching speed. FDV305N.

I welcome you to work on this, if you wish. I am unsure if I will redesign this particular transponder. I might, but I make no promises.

You may have already seen this thread, but if not, check it out: http://www.rctech.net/forum/radio-electronics/950717-aethers-ir-transponder-design.html

Thanks for your interest.

EdwardDimaguila commented 8 years ago

Yeah, looking closely at the schematic. i see what you mean now.