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Show HN: Online oscilloscope with waveform generators

csurgay.com

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Ultimate test: can I plug in the audio from http://www.lofibucket.com/articles/oscilloscope_quake.html as a signal?

That would be a helluva easter egg to put in function generator...

I tried it by using the microphone input looped to an audio device monitor and playing the downloadable (wav) for scope-quake. The scope locked up and would not respond until I reloaded the page. Maybe it works for you? Give it a try.

Nice looks.

It's hard to figure out how to use the features other than just tweaking the generated waveforms.

How to measure anything?

Tried to use Mic as source, the whole thing gets unresponsive and needs a reload. It's in Firefox, Ubuntu.

Also, no sound output when Monitoring is On.

Here are some "discoveries":

- key C (calib) opens a test panel with additional buttons. Selecting Preset2 displays some funny figure. Other Presets are fun too.

- key F (frames) shows red bounding boxes on all controls

-key D (debug) shows some information in Developer console, then needs reload

P.S. Selecting Mic as source throws an exception:

"Uncaught TypeError: navigator.getUserMedia is not a function" in getUserAllow

There's a lot of attention to detail here! I used to have a clunky analog oscilloscope and I see some subtle but important behaviors in the model like the bloom when the intensity is turned up. It seems that to control the knobs I'm supposed to click and drag up and down instead of side to side. Couldn't figure out how to get the FFT to show up, but everything else looks good.

For FFT:

FFT: On

Mode: Add

Trigger: Math

See also

http://www.falstad.com/circuit/

https://cardinal.kx.studio

Something's off with trigger, setting it to channel A when both channels generators run at different frequency should make the second channel waveform "float" as it is unsynchronized. Normally those 2 channel scopes have per-channel trigger source

Here is how mine looks: https://i.imgur.com/TunVxDm.jpg

Is it possible to use probes?

I thought it was neat until I pressed the "Preset" button on the left. Do yourself a favor and try it.

Not sure what was not neat about the demo style credits! Were you disappointed that there weren't any actual presets?

Try pressing preset a few more times…

Interesting. It can play the waveform! Where can I see the source code?

I have a small demo for Sine Wave Scope made with WebGPU here:

https://stackblitz.com/edit/vitejs-vite-cuc9vs?file=main.js

why is this so stationary? I had worked with real oscilloscopes, and it's always tricky to get a steady picture, especially on the old analog ones. But here, no matter what I do, the picture is rock solid.

Two slightly detuned generators added up? Somehow beat frequency does not appear.

Mess with trigger? Real scope would either switch to "auto" mode with wildly changing signal or have picture disappear entirely. Here, it's basically no effect.

It would be interesting to know what exact browser it is supposed to work with.

Nice graphics though, are very many of the control knobs supposed to be functional?

Not sure I would like a software version + audio interface more than the real thing, but this one would make a great addition to simulation software.

Nice! Could it get a signal from the microphone?

Vertical -> CH2 -> Src: Mic worked for me (but not the same for CH1).

CH1 mic worked for me, but only after I also turned on CH2 mic. CH1 mic turns off if CH2 mic turns off.

But you can see both channels work (if both are on mic) by sliding the position of one of the channels. Not certain if it's actually using stereo input on my mac, but they are different. I couldn't do anything to deliberately make one louder than the other.

It quickly locked up on me, or at least responds very slowly. I'm curious, what kind of UI is it using? Canvas? SVG?

tried to connect a probe from my screen to the board I'm testing. Didn't have any luck :(

This is so cool, pressed the ON button out of curiosity and its fully working(!!!) thing

Kudos to author

How fun! I love how the numbers look like they are on vacuum-fluorescent displays :)

The knobs are frustratingly hard to use on a 4k screen.

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