Domain: Engineering — Communications Engineering
Target concept: ASK Amplitude Shift Keying Modulator

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

Evaluation guide:
(i) Target concept: Visual isolation and simultaneous display of the baseband digital signal and the unmodulated carrier in an ASK system setup.
Minimum mechanism: Signal generator must produce discrete high/low voltage states; carrier source must output a stable sinusoid; oscilloscope must support dual-channel acquisition with independent vertical inputs and a shared timebase.
(ii)Storyline: Frame 1–2: Signal generator powered and configured (square wave icon/label visible); Frame 3–4: Wiring from generator → ASK modulator input established; Frame 5–6: Carrier source connected to modulator carrier input AND to oscilloscope CH2; Frame 7–8: Signal generator output additionally tapped directly to oscilloscope CH1 (the same baseband signal that feeds the modulator, shown before modulation); Frame 9–10: Oscilloscope activates dual-channel view showing CH1 (square) and CH2 (sinusoid) side-by-side, all connections remain continuously visible, no occlusion, no repositioning. Perspective: fixed frontal lab bench view, eye-level, full-device framing, no cutaways or zooms.

Manual:
Experimental Procedure
1. Power on the signal generator and set it to produce a binary square wave output.
2. Connect the signal generator's output to the ASK modulator's signal input.
3. Connect the carrier source to the ASK modulator's carrier input.
4. Split the signal generator's output so it also feeds oscilloscope CH1 directly, before modulation; connect the carrier source directly to CH2.
5. Enable dual-channel display on the oscilloscope.
Observation of Experimental Phenomena
- CH1 displays a clean binary square wave (flat high/low voltage levels, sharp vertical transitions) — the baseband signal feeding the modulator.
- CH2 displays a continuous sinusoidal carrier wave (smooth, periodic, uniform amplitude) — the unmodulated carrier feeding the modulator.
- Both waveforms share an identical horizontal timebase and stable timing alignment.
Summary of Experimental Principles
ASK modulation varies carrier amplitude according to the binary baseband signal: high amplitude = logic 1, zero/low amplitude = logic 0. This demo isolates the baseband signal (CH1) and the unmodulated carrier (CH2) — the two inputs to the ASK modulator — to clarify what is being combined before modulation takes place.

Prompt Grounding rubric:
level_1: None of the three devices (signal generator, ASK modulator, oscilloscope) appear anywhere in the video.
level_2: At least one device appears, but the oscilloscope screen shows no square wave and no sinusoidal trace at all, or shows only a single trace instead of a dual-channel display.
level_3: The signal generator, ASK modulator, and oscilloscope are all shown; the oscilloscope screen shows two separate traces side by side, one that looks like a square wave and one that looks like a sinusoid; but it isn't clear which trace is CH1 and which is CH2, and no wiring is shown between the signal generator and the modulator.
level_4: All three devices are shown with correct, recognizable shapes; the oscilloscope shows two clearly separated traces, one on CH1 and one on CH2; CH1 shows a flat-topped square wave with sharp vertical edges, CH2 shows a smooth continuous sinusoid; a visible wire runs from the signal generator's output to the modulator's input; but no wire is shown running to either oscilloscope channel.
level_5: All three devices are shown with correct, recognizable shapes; CH1 and CH2 are clearly distinguished, with CH1 showing the flat-topped square wave and CH2 showing the smooth sinusoid; visible wiring shows the signal generator's output branching to both the ASK modulator's input and directly to oscilloscope CH1, while the carrier source's output branches to both the modulator's carrier input and directly to oscilloscope CH2; all wires stay visible and unmoved for the whole video.

Scientific and Causal Correctness rubric:
level_1: No square wave appears on either channel and no sinusoid appears on either channel, or both channels show the exact same waveform shape.
level_2: One channel shows a wave that's roughly square but with rounded corners or sloped edges instead of flat plateaus and sharp transitions; the other channel shows a shape that is neither a clean square wave nor a clean sinusoid.
level_3: CH1 shows a square wave with flat high/low levels and sharp vertical edges; CH2 shows a smooth sinusoid; but the two are not aligned on the same timebase, or CH1's waveform looks amplitude-modulated (gated on and off) rather than a plain square wave.
level_4: All conditions for score 3 are met, AND CH1 and CH2 share the same horizontal timebase with their cycles staying aligned throughout; CH1's square wave never shows amplitude variation, staying pure baseband; but nothing in the video visually demonstrates that these two channels are the modulator's inputs, since no shot shows the modulator's own output for comparison.
level_5: All conditions for score 4 are met, AND the ASK modulator is shown active (e.g., a lit status indicator) positioned between the two traces in a way that makes clear CH1 (square wave) and CH2 (sinusoid) are its two input signals rather than its output; CH1 is never shown as an amplitude-varying waveform, and CH2 is never shown as anything but a constant-amplitude sinusoid.

Spatiotemporal Consistency rubric:
level_1: Any of the three devices jumps to a new spot on the bench between frames; the oscilloscope screen shows completely unrelated content from one frame to the next; a waveform trace jumps sideways or vertically with no continuous motion; a wire disappears and reappears without being touched.
level_2: A device changes size or orientation abruptly between frames; a waveform trace appears or disappears mid-screen instead of scrolling on or off smoothly; a wire visibly breaks apart and reconnects within the same shot; the room lighting swings from bright to near-dark with no visible cause.
level_3: A waveform trace briefly freezes in place for a couple of frames and then jumps ahead; a wire momentarily crosses in front of and hides a channel label for a few frames; something in the background shifts oddly behind the otherwise-still devices.
level_4: All three devices stay in the same relative positions on the bench; both waveform traces scroll or hold steady smoothly with no freezing or jumping; every wire stays visible along a consistent path; the lighting on the devices doesn't shift, except for one brief moment where a channel's waveform update and its device's indicator light seem very slightly out of step.
level_5: All three devices keep fixed positions on the bench for the whole video; both waveform traces update continuously with no freezing, jumping, or stuttering; every wire stays fully visible, unbroken, and the same thickness along its whole path; the lighting and any reflections on the device surfaces stay consistent and believable throughout, with no sudden shift in position, size, orientation, or brightness of any object.