How can I control my Nakamichi receiver w/ the Radio Shack 15-1994? There is one code in the manual and it dosent work. I did use the 4 special function buttons, using one to turn it on and off, one to control volume up, and one down. I'd rather have the full functions available. Help!

I presume you used learning on the 4 special function buttons, right? Well, although the Radio Shack manual doesn't tell you this, you can learn to almost any button, including volume up, volume down, and power. See the improved 1994 manual at:
[Link: hifi-remote.com]
If you have some electronics ability, you could build a JP1 interface to program your remote from your computer, and you could probably create a Nak upgrade that would give you full functionality. See
[Link: hifi-remote.com]