A compact video delay line

An improved design of distributed parameter video delay line is discussed in which small size is achieved with better frequency and time domain characteristics. The device consists of the tandem connection of unit sections each of which is a distributed delay line of proper length using ferrite cores both inside and outside of the coil. This construction permits larger diameter of delay line with improved transfer characteristics, and consequently larger time delay can be obtained in shorter length. The experimental results show that a 1 μS delay line with 3 Mc bandwidth is constructed for about 2 inch length with little waveform distortion.