I just designed this schematic about a multiple oscillator (that is similar to a chorus or something like that) using 558 chips that I understand are like 4 555 but I never tried them so I would like to see if you consider my diagram correct or not
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This looks interesting! i cant say if its “correct” or not though. 
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Build and see! JFDI badge from me if you do. (I must get round to making some)
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Yeah, build it on a breadboard and then come here for advice to debug it. Nobody wants to bother debugging a schematic because it’s intangible.
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You can from a schematic but real world is easier and a lot of fun. Good luck.
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- I beg to differ
but I get what you mean lol
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It’s a quad 555 with common reset and control voltage shared between the four timers to save pins.
Here’s the pinout if anyone feels like analyzing the circuit but is too lazy to look up the datasheet.
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Didn’t analyze the circuit much, but having the capacitors connected to VCC by default doesn’t seem right.
The outputs on the lower left side are all connected together and not connected so as to discharge the capacitors, it doesn’t look like that part of the circuit would oscillate.
Edit: also: only 8 capacitors for 16 timers, what is your intent here?
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Also obsolete since ~20 years or so.
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I had doubts since in the 555 and 556 the pins are labeled as discharge and threshold too triger and out; but in the 558 it appears simplified that of timing instead of discharge or threshold and I don’t know what it refers to. I also understand that if you do not place a capacitor the chip will oscillate to the maximum then maybe only the resistors are enough (I don’t know if I should include the capacitor in the middle of these). the outputs all come together to give a chorus effect (with the resistors r1 r2 r3 r4 with different values) but I don’t know if I need a diode so that strange things don’t happen as it is, I haven’t tried it yet because I recently research about these chips and with the quarantine I don’t think I can go buy one
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Amazingly these 558 quad timers are still available on eBay but the prices are eye-watering. The cheapest, from UK stock, is ÂŁ1 each and ÂŁ2.64 postage. 555 timers go at ÂŁ1.70 for 5, postage free. 556 dual timers are ÂŁ1.79 for 5 or ÂŁ13.99 for 50, postage free. All items UK sourced via eBay.
Oh funnily enough I’m working on the A10P10C10, and the A100P100C100 respectively. The ladder is probably going to most likely end up being a white noise generator but hey, it’ll be cool to own personally.
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