1971: NAP 160
chrome bumper, boards mounted vertically, power transitors mounted in the back of the unit, four power diodes mounted in middle of chassis
chrome bumper, boards mounted horizontally, power transistors mounted in the back of the unit, bridge rectifier mounted in the middle of the chassis
olive series, new board layout, power transistors mounted on circuit boards
1973 – 1975: NAP 200
1974: NAC 12
1975: NAP 250
1978: NAP 120, EI transformer, power switch on the rear, boards mounted vertically.
1979: NAP 120, toroid transformer, power switch on the front, boards mounted horizontally.
1979: NAP 110