6 Klark Tecknik DN27A in for work. Its amazing to me the changes over the years. 2 units have input transformers and output transformers. The two will transformers will get a electrolytic cap change and general inspection. Of the four remaining, the most similar two will get Jensen input and output transformers, cap change and inspection. One unit had permanent power cord modification, that is going to get changed back to the original style power connector.