Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: Christopher Howard <christopher@librehacker.com>
Newsgroups: sci.electronics.design
Subject: Re: signal leads that pick up less ambient noise?
Date: Fri, 21 Feb 2025 10:14:03 -0900
Organization: A noiseless patient Spider
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I wanted to mention that this morning I moved the old PC computer box
about ten feet away from my work station, and that reduced the noise
down immediately to about 100 mV p-p, from the original 500 mV p-p.

After doing that, I tried running the signal from the signal generator
through a simple lowpass RC filter, with R=200Ω and C=1µF. This drops
the noise down some more to about 40 mV p-p.

I also moved the signal generator closer and am using some very short
leads with alligator clips. This doesn't seem to have much effect on the
noise, as far as I tell, but it seemed like a good idea in principle.

I like the idea of putting my analog computer inside a metal box, but I
don't currently have a spare metal box, and also that would hide all the
switches, trim pots, and terminals. I have an idea though of moving this
direction later after building some kind of patch panel. I also wonder
if it might be helpful at least to have the bottoms and sides of the
analog computer surrounded by metal, i.e., set it inside an open metal
box.

-- 
Christopher Howard