The WFM 601 is a half-rack width by three rack unit high serial component monitor. It employs a bright, white phosphor, post accelerated CRT with lighted internal graticule. The parallax free internal graticule structure contains markings for waveform functions. The lightning, diamond, vector, and audio graticules are electronic, in order to keep from complicating the waveform graticule. The monitor is microprocessor controlled to provide greater versatility. Switch settings that affect the operation of the instrument are continuously polled by the processor, with any change in status acted upon immediately. Current operating conditions are preserved in Non-Volatile Random Access Memory (NOVRAM), which returns the front-panel settings to current ones, in the event of power interruption (either accidental or routine power down). Many of the operational measurements are performed on a repetitive basis. These instruments provide a method of repeating common measurements by selecting stored measurement settings from a CRT menu list. The operator can store and name up to 9 common measurement front-panel settings. Measurement specific front-panel settings can then be recalled by pushing the Preset Menu and selecting the desired preset by name or number. Many of the functions that were formerly selected by changing internal jumpers and/or wire straps are now accessible through on-screen menu selections. They are selected by pushing the appropriate front-panel menu select button. Menu items are then selected by pushing one or more of the assignable switches and/or turning the assigned front–panel control. Once selected these menu choices are retained until changed by subsequent reconfiguration, or turning off the function with a MENU button. The front panel provides both assignable switches (located next to the CRT) and controls (located beneath the CRT), that operate with CRT readout to increase functionality without cluttering the limited front-panel area. Function of these switches and controls is dictated by the front-panel display and initial menu choices. The WFM 601 is capable of measuring and monitoring 4–2–2 component serial digital. It incorporates a straight through (non-filtered) display or a differentiated step filter. The assignable cursors, along with the CRT readout can be used for time and voltage measurements. The system of menus and CRT readout simplifies the configuration of this monitor for measurement or monitoring of signal characteristics. The following list composes the feature set for the WFM 601. GBR or Y PB PR display format. Any or all of channels 1, 2, or 3 displayed. Parade or Overlay display. Flat or Diff’d Step filtering. X1, X5, X10, and Variable display gain. X25 Magnified sweep. 1 and 2 Line or Field sweep. Bar Cursors; amplitude, time, or amplitude + time, +marker. Line Select with readout; 1 line or 15 line, all fields or 1 of 2 fields. Picture Monitor Out with bright up (on Y or G channel only). Vector Display; fixed or variable gain, 75% or 100% bars, SMPTE/EBU N10. Lightning or Diamond display; vertical gain (same as waveform), horizontal gain fixed, magnified, or variable, 75% or 100% bars, SMPTE/EBU N10. Electronic graticules for Lightning, Diamond, Vector, and Audio displays. Displays audio input from the REMOTE connector as a lissajous pattern. Monitor Output; GBR or Y PB PR (follows A/B switching), gamut error bright up. EDH: (Follows A/B switching) LED for presence and an alarm, rear panel TTL low through the REMOTE connector. Reclocked Serial Component Digital output following A/B switching. Video Reference: Internal Serial Component signal (follows A/B switching), External Composite.