For future referance, You could also have plugged the headphone out on your keyboard to the aux or line in on your sound card on your computer. Then you could record directly into your pc, rather than a tape. Course its not as porable. there is also a mic in on most sound cards, but you wouldnt want to use that.
Yeah, I already tried it the first time with the Casio volume set on, like, Normal, and the resulting tape registered on the seismograph over at the U of I. 
But I’ll try it with the “Aux” input next.
Ah, just FTR, I tried plugging it into the “Aux” jack and it worked even better–for one thing, it didn’t need to have the volume turned way down to practically off, and even better, it didn’t also record a loud electronic hum until the music actually started recording, which is what plugging it into “Mic” was doing.
Technology… :rolleyes:
I also went and looked at the manual (dug it out of the trash can, actually) and it says the “Aux” jack is for “alternate audio input”, like CD players, radios, etc. So, huh. The Radio Shack guy wasn’t totally wrong, but he wasn’t totally right, either. “Mic” works, but “Aux” is better.