Domain: Engineering — Communications Engineering
Target concept: PSK Modulator

Video generation prompt: The signal generator outputs a binary square wave signal, which is connected to a PSK phase-shift keying modulator. The oscilloscope's dual channels display the digital signal and the carrier signal, respectively.

Evaluation guide:
(i) Target concept: Binary digital control of carrier phase via hardware PSK modulator.
Minimum mechanism: Signal generator must produce discrete high/low voltage states; carrier must be a stable sine wave; modulator must accept both inputs and output phase-shifted carrier; oscilloscope must resolve both baseband and RF signals simultaneously on dual channels.
(ii)Storyline: Frame 1–2: Signal generator and carrier source visible, cables extending toward PSK modulator. Frame 3–4: PSK modulator shown with two input cables (data + carrier) and one output cable. Frame 5–6: Oscilloscope appears with two active channels. Left half shows square wave, right half shows sine wave; both traces are stable, non-overlapping, and horizontally aligned. Frame 7–10: Continuous view holds fixed spatial layout; no device moves; waveforms scroll leftward uniformly; no new objects enter; no causal reversal (e.g., modulated output never precedes input connection). Perspective is fixed frontal view of full bench setup; all critical elements (device fronts, screen, cables) remain fully visible and unoccluded.

Manual:
Experimental Procedure
1. Connect signal generator output to PSK modulator data input.
2. Connect carrier source to PSK modulator carrier input.
3. Tap the signal generator's digital output directly to oscilloscope CH1 (before it reaches the modulator, as a verification point); connect the carrier source directly to CH2.
Observation of Experimental Phenomena
- CH1 displays the binary square wave (two-level, rectangular) driving the modulator's data input.
- CH2 displays the pure sinusoidal carrier (smooth, periodic) feeding the modulator's carrier input.
- Both waveforms appear simultaneously, side-by-side on the oscilloscope screen, showing the modulator's two raw inputs rather than its modulated output.
Summary of Experimental Principles
PSK modulation encodes binary data by shifting the phase of a carrier sine wave; before that shift can happen, the modulator needs a clean baseband digital signal and a clean sinusoidal carrier as its two inputs — this is what the oscilloscope's two channels verify here.

Prompt Grounding rubric:
level_1: None of the three devices (signal generator, PSK modulator, oscilloscope) appear anywhere in the video.
level_2: At least one device appears (for example, only the oscilloscope), but no binary square wave appears on any channel and no sinusoidal carrier trace is displayed anywhere; or the devices are shown with no visible wiring connecting them at all.
level_3: The signal generator, the PSK modulator, and the oscilloscope all appear on screen; the oscilloscope shows two channels at once, one with a two-level rectangular (square) waveform and the other with a sinusoidal waveform; a cable is visible running from the signal generator toward the modulator's data input, a cable is visible running from the carrier source toward the modulator's carrier input, and a cable is visible running from the signal generator (or carrier source) to the corresponding oscilloscope channel.
level_4: Everything at level 3 holds, and in addition the two oscilloscope channels are either labeled (e.g., 'CH1: Digital Signal', 'CH2: Carrier') or otherwise unambiguous: the square wave and the sine wave are both visible at once with stable, non-overlapping traces, no flicker, no missing trace segments, and no swap between which channel shows which waveform.
level_5: Everything at level 4 holds, and in addition the square wave keeps sharp vertical edges and flat tops/bottoms with no rounding or overshoot, the sine wave stays a clean, continuous curve with uniform amplitude and period, neither trace visibly slides left or right relative to the other over time, and every cable visibly enters and exits a real port on a device with no floating or physically impossible routing.

Scientific and Causal Correctness rubric:
level_1: Both oscilloscope channels show visually indistinguishable waveforms (e.g., two identical square waves), the carrier channel's trace is square or triangular instead of sinusoidal, the digital channel's trace shows more than two distinct voltage levels, or nothing in the scene suggests any relationship to phase-shift keying (e.g., no PSK modulator is depicted at all).
level_2: The digital trace shows three or more distinct voltage levels instead of a clean two-level square wave, the carrier trace is missing or replaced by noise or a flat line, or the PSK modulator is shown but has no visible carrier-input connection.
level_3: One oscilloscope channel shows a two-level rectangular (square) waveform and the other shows a smooth, single-frequency sinusoidal waveform; a PSK modulator is visibly present, receiving the digital signal and the carrier as its two separate inputs; neither trace shows distortion that breaks its basic identity (e.g., the carrier's peaks are not clipped, the square wave's pulse widths do not collapse to near zero).
level_4: Everything at level 3 holds, and in addition the two inputs feeding the modulator are visually distinguishable from each other (e.g., two separate cables enter the modulator, one carrying the square wave and one carrying the sine wave); no channel is mislabeled relative to what it actually displays (e.g., a channel marked 'carrier' does not show a square wave).
level_5: Everything at level 4 holds, and in addition the digital and carrier traces share the same horizontal timebase so their relative timing can be compared directly; the carrier trace shows a constant, unbroken sine wave with no phase discontinuities anywhere in the video, consistent with being tapped ahead of the modulator as a clean reference rather than the modulator's phase-shifted output; and the digital trace's edges align with a data rate that is physically plausible for driving a PSK modulator (clearly slower than the carrier's own period, not a rapid flicker).

Spatiotemporal Consistency rubric:
level_1: The signal generator, modulator, or oscilloscope jumps to a different position between frames; the oscilloscope screen's waveform vanishes and reappears with a different shape from one frame to the next; the overall lighting shifts abruptly; a device's orientation flips with no visible motion causing it; or a cable disconnects and reconnects with no hand or mechanism causing it.
level_2: The oscilloscope trace flickers on and off unpredictably across frames; the modulator's casing visibly stretches or warps; a cable connection blinks in and out of view; background objects shake violently frame to frame; or the camera viewpoint rotates or zooms with a visible jump rather than a smooth pan/zoom.
level_3: The signal generator, modulator, and oscilloscope stay in the same relative positions throughout; the oscilloscope screen shows stable, continuously present waveforms in every frame; every cable keeps a consistent shape with no stretching, snapping, or vanishing segments; no cable appears behind the modulator in one frame and fully in front of it in the next with no motion explaining the change; and no device surface shows a sudden, unexplained change in lighting or shadow.
level_4: Everything at level 3 holds, and in addition both waveform traces move across the screen smoothly with no stutter, skipped frames, or sudden jumps; the device casings stay rigid with no bending or melting; every cable's curve and the angle where it meets a port stay constant; and front-panel text and labels stay legible and undistorted as the camera view changes.
level_5: Everything at level 4 holds, and in addition neither trace ever appears duplicated or ghosted from one frame to the next; the square wave's edges and the oscilloscope's graticule lines look clean and steady rather than crawling or shimmering; cables consistently pass behind or in front of the devices exactly as the camera angle dictates, with no layer popping to the wrong side; and the two channels' traces scroll or refresh at the same visible rate, with neither one lagging behind the other.