[sdiy] More beginners questions

[mikael at mikmo.dk]

Thanks for all the nice replys to my beginners project question. That gave me a
bit to think about :-)

I have a couple more questions

While searching for some IC's i got somewhat confused over the naming of these
little buggers.

If a schematic calls for a LM13700, can i the safely assume that an OTA called
LM13700N is the same ? Is the alphabetic postfix just different manufacturers
"tags" ?  And does the same go for TL084 and TL084CN ? and so on...

And now for something compleatly different

I can see that a scope is more or less required for calibrating and
troubleshooting anything but the simplest circuits. What minimum options should
i look for when shopping for a scope for synth DIY work ?

20 Mhz or better ?
Single or dual trace ?
Other important features ?
Any brands i should stay away from ?
Is "safe" to by a second hand scope ?

Thanks for your patience

Mikael