----- Original Message ----- From: David VanHorn To: > 1: bypass the pic properly. 0.01uF has lowest impedance around 4 MHz, you > may need 0.0033 for third harmonic supression, and a 0.1 or even a 1uF for > slower events at higher currents. I never did know exactly how to estimate what value of bypass would be adequate... I just always used 0.1 because it's what I mostly saw, and when I'd hear of using something 1uf or higher I'd always wonder why... > 2: pic's power and ground should route back to the power supply separate of > anything else. (I separate the micro's supply track, and route power > through an EMI filter ($0.25) to the bypass cap located at the uP ground > pin, and there on to the VCC pin. It's a compromise, but it works. Ground > is flooded.) I'm also only now just learning about how to lay out a board properly. I'll keep this in mind and try those things mentioned. > Which scope did you get exactly? I bid on a Tektronix 2335 100MHz, which according to the manual (luckily I won a bid that included everything, manuals, probes, front cover, top pouch) is dated around 1980 or 1981, and it was all clean aesthetically and clean working controls. The only thing I don't like about it is there is no graticule illumination. Already for just the few days I've used it, I've found myself saying I wish I could light up the scale and see where it's peaking. But that's ok, this was only meant to be a toy scope, if there is such a thing...when I get the real thing it'll definitely have all the on screen stuff (I don't even know if there are many new analog-only scopes around anymore) etc. I like features like run-stop to pause the jittery waveforms and look at them but still, there's nothing like a nice pure analog scope screen. I've been using in the lab, a Fluke combi scope analog/digital selectable, but it always looks like a stepped sine wave on the screen....I hate that.