This is a history of Michael's Power-Supply problem and fixes:
Page 0 -- Correspondence with K7JEB on Power Supply Failure
Page 1 -- Scan of Heathkit HP-10 Info
Page 2 -- Baseline Schematic and Analysis
Page 3 --
Redesign into Darlington Configuration
Page 5 -- 2N1147 Transistor Data
Page 9 -- HP-10 Power Supply Photo
Page 11 -- Darlington Connection Photo