Here we see an assembled pre-amplifier being calibrated and tested. At this point each individual amplification stage is carefully fine tuned for optimum performance.
Then all stages of the amplifier are calibrated. The behaviour of the amplifier is analysed and then optimized for performance. Power amplifiers are checked at all power levels and with various loads.
Amongst the multitude of checks, calibration procedures and measurements, the action, speed and performance of the protection systems are examined under various conditions.
Many pages of measurements are taken and a test report is written out for each unit documenting in detail the amplifiers capability and characteristics.