iglou-eu / open-stylophone Goto Github PK

Whatever you do, don't use an ordinary '555. Use a CMOS version, like TI's TLC555CPSR. The older bipolar '555s are terrible to work with. They generate huge transient loads on their supply pin when they change states, requiring at least 10µF of bypass

Reddit - AGuyNamedEddie

You need at least some bypass on U1. Another 1µF cap like C4 will do nicely.

Reddit - AGuyNamedEddie

C7 is backwards. The + terminal should face the driver, like C9.

Reddit - AGuyNamedEddie

• Replace jack connector to SMD low profile
• B out channel is connected ... but this is a MONO output ...

Replace most of "Extended Part" by "Basic Part".
Keyboard require 1% Resistors.

Why ?

JLCPCB (If you're using them) has "basic" and non-basic components, the difference being basic components don't charge a reeling fee, so theoretically you can get boards made for a lot cheaper if you have all basic components.

Reddit - f0urtyfive