4 ms·
I guess he also believes that 50 MHz or so signals can be measured reliably on a 40 MHz (on paper at least) scope.
by elch 5mo ago
I guess he also believes that 50 MHz or so signals can be measured reliably on a 40 MHz (on paper at least) scope.
- PunchyHamster 5mo agoMost digital scopes have around 5-10 times faster sampling than bandwidth. The one on pic is 250Msps. That's more than good enough for the purpose of checking interference
- elch 5mo agoBut he tries to quantify this interference. Anyway Animats's comment is the one that points IMHO to the most likely cause of the observed waveforms. https://news.ycombinator.com/item?id=47931024 https://news.ycombinator.com/item?id=47931024 PS Now that I’ve taken a closer look, this is even sillier than I first thought. He’s hunting for 50 MHz ghost signals by connecting his PCB to a breadboard using (crappy) wires that are at least 10 cm long. And he’s connecting the scope probe to the breadboard (or those breadboard wires). And if I’m not mistaken, he doesn’t even bother to connect the ground lead of the probe.