Re:
You've stumbled across the hyper-rare TA "BCDMaster" crankset. There was a feeling in the late 70's by some of the engineers at TA that the proliferation of excessively many different bcd standards in cranksets had gone far enough. It was at this point, they released the "BCDMaster" crankset, with drillium holes for every bcd standard available in 1977.
Today the sons of these very same engineers (it's nepotism incarnate) have done much the same thing with the TA Carmina cranksets, which echoes the now very famous "BCDMaster" design.
- Don *grin* Gillies
San Diego, CA