Wow, it sounds like it could be a Schwinn Voyageur!
The Voyageur was a very nice bike, right below the Paramount in the Schwinn hierarchy. The frame should be double-butted chrome moly steel. The drops on a Voyageur are forged, not stamped plate, as was the case on lesser Schwinns.
So to narrow the models down a bit do this:
1) Look for forged drops front and rear and,
2) Thump the top and down tubes with the nail side of your index finger.
If the drops are forged and the tubes sound really thin, I think you may have a Voyageur. Or, you may possibly have a Le Tour 12.2, which was the weight of the bike in kilograms. Either bike is worthy of complete restoration!
Let us know...