[gh02t]

Yeah, in the article he uses a good old MAX3232, which is specifically for doing RS232 to TTL level shifting. Totally agree, the Saleae or one of the cheaper clones I linked is a better choice for most hobbyists. Scopes are indispensable for certain uses, but most Arduino/RasPi projects these days are all digital and you can do everything you need with a logic analyzer + a decent multimeter.

I use my scope just often enough that I'm glad I have it, but I sometimes also regret buying it because it's not that often that I actually need it.