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A comment on Ask HN: Most interesting tech you built for just yourself?. Parent comment

Re:Ask HN: Most interesting tech you built for just yourself? by hcrean on Friday April 28, 2023 @08:53AM (#35740687)
Pico caps and appropriate impedance miss-match can be used to round-off square waves.

But yes, if you look at high-speed Pi GPIO with a Rigol it looks more like an EKG readout than the thing you might see on a logic analyser. Smoothing it enough to feed a line-amp is very lossy.

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Re:Ask HN: Most interesting tech you built for just yourself? by megous on Friday April 28, 2023 @10:01AM (#35741360)
You might want to improve your probing technique, then. :)

GPIO's usually looks quite squarey if you don't introduce parasitic reactances into the circuit with your test setup.

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Re:Ask HN: Most interesting tech you built for just yourself? by hcrean on Friday April 28, 2023 @03:41PM (#35746144)
Pi for audio frequencies is lovely and square, Pi at radio frequencies has distinct rise and fall and "just taking a moment to think about it" segments.

A spectrum analyser has probes!?!? This might be where I am going wrong... But the bench scope is largely in agreement about the distinct phases of a cycle at RF freq.

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