A production unit of a new, completely self-contained device for measuring optical transfer functions will be demonstrated and explained in detail. Some of the remarkable features are: A simple photocell is employed instead of a photo multiplier because of the high efficiency of the optical track. It has a unique attachment for exact spatial zero frequency measurements. It has a built-in oscilloscope and a recorder capable of taking a complete diagram every 20 seconds. It works with one single electrical frequency of 400 cps and therefore eliminates the higher harmonics without the necessity of a sinusoidal target. The instrument can be operated by a technician without any special optical knowledge.