Using marbles gate in circuit...weird edges with xor'ing with a button

hey,
I’m working on designing a gate in circuit for a modified version of the ciat-lonbarde gerassic organ paper circuit I’m trying to design and build.

basically, it’s the marbles gate-in circuit, combined with a momentary button that it is xor’d with. I am using a pot to act as a variable resistor, which seems to set a threshold for the gate in. I updated the resistor from the marbles schematic that pulls down +V from 100k to 220k because it seemed to allow more of the full range of the threshold pot. the simulator doesn’t show it, but It goes from pretty much a 0v to ~10v threshold, so you can effectively mute or “always on” the gate (both with a gate signal in and with nothing patched in).

simulator: http://tinyurl.com/y7yz9dr5

from the output of the xor, when the button is low I get nice crisp edges on my scope:

when the button is high, they are much more “fuzzy”…it seems to go haywire for a second when it’s going between low and high:

Do you know what might be the cause of this weirdness?


(Also, I haven’t been able to get the LED to work yet…still trying to figure that out.)

This is called switch bounce. You need to add a filter for that.

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…when you realize you’ve been using 557 instead of 547 transistors the whole time you’ve been breadboarding this:

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working perfect now! simulator here

thanks for that tip on it being called “switch bounce”…i tried googling a ton of “fuzzy logic, not sharp edges, etc.” terms and could never find anything.