Altair 680 power supply...

My Altair 680 has achieved the position of primary attention on my workbench. All of the ICs are socketed. Not having seen power in over 20 years, I did not trust the power supply as far as I could throw a bus. I pulled all of the ICs, attached dummy loads (automobile bulbs) and powered up. Sure enough, there was AC all over the place (where there should have been DC). I replaced all of the electrolytic caps and that got rid of the AC but some of the voltage levels are very wrong, at least as compared to what is written on the schematics. The worst offender is just off the "plus" side of the full wave bridge (BR-1). It should be nine volts but is actually at 11.5. This makes what should be the main five volt rail a little more than 9 volts... the far side of VR-1 (a 7805). The wave form coming off the transformer is really ugly not a smooth sine wave. I hate power supplies. I don't really understand, looking at the schematics, what this transformer should be doing. My guess is that it should be making a nice nine volt, 60 cycle AC sine wave with each of the two outputs 90 degrees out of sync? What could be wrong with a transformer that it would produce something like: __ / \ | \ / \_ / \ | / | / \_/ bent and very squared off at spots? My scope shows nice clean 120 coming into the transformer. How do I figure out a part number for a replacement transformer? Thanks!