Repairing an Oltronix B602D Power Supply This is a repair/maintenance description of a 70's linear bench power supply. Oltronix LABPAC B602D. I bought this old power supply from a scrap dealer. Haggled a bit and got a good price. It's a nice 70's linear laboratory power supply with two channels, 0-30V 1.4A and 0-60V 0.7A. The two channels are fully independent with isolation voltage between them and chassis +-500V DC (according to the manual). And it has a "digital" voltage display! Oltronix was a company that was based in Sweden that made high end laboratory equipment. Parts of the company still exist and are based in the Netherlands. There is a similar three channel model B603D that has an additional 6V power supply. I opened it an cleaned some dust, before powering it on. Take it apart (as Dave Jones says)! It didn't look too bad. So I then powered it up. The 0-30V channel worked fine. But the 0-60V channel did not. So I began some more detai...