Are there any open source oscilloscope projects for the raspberry pi?

Question

Raspberry Pi

I want to make a good oscilloscope (up to tens of megahertz). At first I wanted to use adruino mega, but I realized that the speed would not be enough, and even without a computer it would be difficult. In raspberry pi and beaglebone black, which can be easily connected via HDMI to a TV or monitor, there is no loss in data transmission to a computer.
All of the above are available, there are even various Soviet operational amplifiers with gold-plated legs (or is it better to use an external ADC?)
In general, tell me, are there any ready-made projects for such devices?

Answer 1

hope it helps
www.bitscope.com/pi
www.open-electronics.org/turn-your-raspberry-pi-in...

Answer 2

There is no ADC input on the GPIO connector on the raspberry pi, so you definitely cannot do without an external ADC. You can, of course, tinker with the board itself and then try to write an appropriate Linux driver, but I doubt that you will be able to pull the sample rate beyond 2 - 6 MHz. As far as I know (maybe I'm behind the times), for smart oscilloscopes, several ADC channels are used, which are interrogated in turn, thereby increasing the sampling rate, since ADCs of tens of MHz either do not exist or are very expensive.