Thanks, guys!  I will try it this afternoon!

Ok, so I was rooting around in my parents' attic and found my very first amp, an old Gorilla GG-20 30 watt amp.  I plugged it in, plugged my guitar in, and nothing happened.  I hooked up my headphones to the headphone jack and it worked.  However, it sounds like my pots must be really dirty, cause it was crackling and buzzing and popping every time I adjusted the volume, gain, etc.  Any ideas on where to start to resolve this problem?  I bought a multimeter shown in the multimeter video on this forum, but I'm at a loss for where to start troubleshooting.  Thanks for any suggestions!