Interesting though perhaps fatally-flawed mystery frame. Mystery because absolutely no symbols (other than Campy Strada crank (diamond-8) w/generic english BB), headbadge holes or decal remnants found anywhere and finish is thick black, powder-coat like.
Interesting because quality touches include nicely-done fastback stays, clean brazing, twin (very sharp) seat tube peaks, thin tubing (and just as thin lugs but more on this later) with 27.2 CampRec post. I think year is 78-83 judging by recessed brake fastening, remaining components and semi-vertical rear DOuts (w/no marking).
The most unique features are multiple brazed-on threaded bosses on seat-stays and fork-legs. Starting 1-1/2" below rear ST peak, binder-bolt goes thru seat stays; then down another 3-1/2" is a pair of rear-facing bosses; further down 1-1/2" are outside-facing bosses (for rack I presume); then another 1-1/2" for brake bridge; down 2-1/2" to another pair of rear-facing bosses and down again another 1-1/2" for final pair of rear-facing bosses. These last two pair of bosses are also found on the fork legs starting 2" below brake-bolt drilling. Could all these threaded bosses be for racks? They seem to be partially covered by brake calipers.
Wide (700C?) tire clearance plus plethora of braze-ons shouts TOURING while 16-3/4" chainstays...perhaps Sport-Touring?
Now the fatal flaw; the business-card-thin lugs are cracked clear thru on both sides of the head and down-tubes, each crack about 1" long with a little separation. Can this junction be fillet-brazed or must the down and head tubes be replaced?
I guess this is what happens when one wishes for the best of both worlds...
Jack Romans
Sacramento, CA