ATtiny15L AM-bug

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Hi!

I'd like to build a mini AM (of FM if possible) transmitter using the 15l's PWM output connected to an antenna and a mic on it's analog inputs. Does anyone know if this is possible? I'd like to use it to calibrate old vacuum tube radio's and to play with :)

AVRblinken code completed very soon!

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Hey Ralph,
I am currently working on taking a mic sample and putting it through a fiber optic cable. I think you might find it useful to check out the app note 335 "Digital recorder". It goes over some basic sampling and output with the PWM channel.
I think you are going to run into difficulties with the AM generation. AM stands for Amplitude Modulation and this means the input signal is multiplied by a sinusoidal signal. AM range is from approximately 500KHz to 1500KHz. The tiny15 has an internal clock which is approximately equal to the later one. This makes it very hard for your output PWM to represent this signal. I would suggest making the transmitter in analog circuitry. I know there are a lot of plans on the web for this. You can also by modules from Digikey, I have used these for wireless links between controllers.

Good luck,
Ian

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