Delay line

The first Tektronix scope to contain a delay line was the 513D, which uses an L-C network. Soon after, the 517 appeared, using a coaxial cable as a delay line. 7000-series scopes use special twin-lead delay cables. The delay line in the 519 is a large coil of low-loss air-dielectric rigid coax.

Some delay lines are at the input. Some are between amplifiers. Some are between the final amplifier and the CRT vertical deflection plates.