Modulators are split into two classes&colon; potentiators and correctors. "coma correctors" for Newtonian reflectors have been designed which reduce coma in telescopes below f/6. A few final tests, using the conventional null correctors, correctly reported spherical aberration. Some pitch correctors can add vibrato. Interleaving is used to convert convolutional codes from random error correctors to burst error correctors. These included time base correctors (TBC) and digital video effects (DVE) units. At least 9 different correctors worked on this codex. The hands of two correctors may be distinguished. In practice, a variety of techniques have been used in the design of phase correctors. There he appointed deputy correctors to represent him in the university. Height correctors act with some delay in order not to correct regular suspension movements. Specialist correctors ensured that texts followed the standards of the time.