
Show HN: PiScope – Turn Your Raspberry Pi into an Oscilloscope/XY Plotter - aaggarwal
https://github.com/ankitaggarwal011/PiScope
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Animats
That's a nice starter project. There are lots of "turn your PC into an
oscilloscope" USB devices, starting around $50 for a 200KHz sampling rate.[1]
For $269, you can get a 2GHz sampling rate.[2] It's hard to justify getting a
dedicated scope any more, unless you need something exotic.

[1] [https://www.bananarobotics.com/shop/Educational-PC-
Oscillosc...](https://www.bananarobotics.com/shop/Educational-PC-Oscilloscope-
Electronic-Kit) [2]
[https://www.sparkfun.com/products/9263](https://www.sparkfun.com/products/9263)

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krapht
Oscilloscope #2 is $269 and has a 60 MHz bandwidth. How on earth is that good
value?

I would like to recommend the Rigol DS1052E in that price range, or a used
HP/Tektronix analog scope for the sub-$100 market.

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rpcope1
I second this, as the proud owner of a Rigol 1102E (and several other scopes),
it's amazing what $400 gets you there. A good scope is about so much more than
just the bandwidth, it's about having a good front end with low noise, and
things like AC coupling, and an easily readible screen. I think if I were to
only be able to own one scope and do it on a budget, Rigol 1XX2E series is
really the only way to go sub-$1000.

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aaggarwal
Hi, I am the author. This is a hobby project. I think it could be a useful
tool for DIYers. Any feedback is much appreciated.

~~~
detaro
IMHO the naming isn't great, because it would be useful for plotting slow-ish
sensor data, but I'd struggle calling something with only ~3kS/s an
"oscilloscope"

~~~
aaggarwal
Thank you for the feedback. I appreciate it.

I understand that it wouldn't compare with the actual oscilloscope, but this
was never meant to be a replacement for oscilloscope. It's just a low cost way
to convert available electronics into a portable handy scope for basic
applications. It was very useful for me while I was designing a
characterization board.

Sampling rate depends upon the analog to digital converter (ADC) used with the
Raspberry Pi. ADS1015 has a relatively lower sampling rate of 3.3kS/s.
However, I have also used MCP3002 with Raspberry Pi. It has a sampling rate of
around 75KS/s for 2.7V (and 200KS/s for 5V), which gives a very good
performance.

So, just with a change of ADC, one can achieve better performance. I will
probably include support for more ADCs in the library soon.

~~~
rpcope1
You might call it a DAQ, since that's much more in line with what you're
doing.

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batou
Looks useful for data logging and general experimental work in low speed
scenarios. I'm currently using a TI 83 silver edition and a TI CBL and some
Vernier sensors for this sort of stuff and it's a bit sucky but was
essentially skip dived.

As a scope though, forget it. You need at least 1-2MHz BW for something usable
for even audio applications. At least 20MHz is probably a good idea. I have a
20MHz analogue scope (LG) and it cost me £10 (~$15) which is less than the Pi.

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69_years_and
Sweet and totally within the spirit of RaspberryPi. Thanks for releasing it.

PS. 3K sample/sec is good enough for a lot of work on sensors and also for the
youngish to get a handle on how to do ADC and process it - who knows some
young person may start of experimenting with something like this and go onto
design something quite awesome in the future.

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rpcope1
In much the same vein, if you've got a little extra cash to cough up for a
cheapo $60 scope (which can be pushed to 20ish MHz bandwidth, or perhaps
better), I've managed to a lot of the similar stuff (in Python) on a Raspberry
Pi with a library I rolled for the Hantek 6022BE:
[https://github.com/rpcope1/Hantek6022API](https://github.com/rpcope1/Hantek6022API)

