No No No! The mains cord is the brown lead. The eyelets and the lever are for setting the mains voltage. IMHO i'd set it round to 127volts, 110volts seesm too low these days for the USofA. I would guess there's a fuse missing from those two clips just to the left of the voltage selector arm, it may tell you on the back panel waht value to use but I'd guess at 2Amps.
The black flat lead coming down from the top of the case is the FM antenna - it should be connected to those two blue plugs left hand side of the chassis rear.
Should sound good with those big speakers and 4 ECL86's to drive them.
Give us a better pic of the front panel pushbuttons se we can see what they say, although if you just press the one marked "UKW" you may hear some FM stations - once you put the fuse in of course! it appears to only go up to 104MHz so you'll miss some US stations. If you see any smoke, pull the plug quick! Don't forget it will take a minute or so to warm up. "AUS" will turn it off.There's a rotating ferrite rod antenna for the BC band, it'll be marked as the "MW" button, you may see another marked "FA" which connects the internal antenna. Expect the switches to be very noisy, hopefully they'll clean up as you use it.