Solar8000 clock¶

The Solar8000 monitor's internal timing of its numeric windows.

Stub

Imported from the time-source table; the full page is still to be written.


Type	unknown
Nominal	Monitor numerics windows
Kept by	Solar8000 monitor

Description¶

The Solar8000 monitor's internal timing of its numeric windows. The values are stamped by the recorder on arrival, so only their delay is seen.

Route to UTC¶

The route the atlas trusts most (3 links; its weakest link is measured apart from the link to UTC that every clock shares):

Solar8000 clock

link measured Solar8000 numerics against SNUADC: drift 0 s/h median (p10–p90 about ±0.5 s/h)

SNUADC sample clock

link measured SNUADC (frequent-correction mode) against the recorder PC: drift −0.954 ppm (n = 6321; census of 6,321 files (17 October): median −0.9535 ppm; 89.5% of recording hours within 0.05 ppm of −0.954; 747 files (12%) between −0.90 and −0.55 ppm)

Recorder PC clock

link assumed Recorder PC against UTC: drift 0.1–10 ppm (assumed); corrected every 8–24 h (assumed)

UTC

Where every route ends.

Independent checks. 3 other routes reach UTC; where they meet, the offsets must close around the loop:

Solar8000 clock (Solar8000 numerics against SNUADC) → SNUADC sample clock (SNUADC (step mode) against the recorder PC) → Recorder PC clock (Recorder PC against UTC) → UTC
Solar8000 clock (Solar8000 numerics against SNUADC) → SNUADC sample clock (BIS against SNUADC) → BIS clock (BIS against the recorder PC) → Recorder PC clock (Recorder PC against UTC) → UTC
Solar8000 clock (Solar8000 numerics against SNUADC) → SNUADC sample clock (CardioQ against SNUADC) → CardioQ clock (CardioQ against the recorder PC) → Recorder PC clock (Recorder PC against UTC) → UTC

Plan. No device clock is visible: the numbers are stamped by the PC on arrival. Their per-case delays behind SNUADC are fixed within a case, which bounds the monitor's drift. To strengthen: the monitor output clock (240 Hz line) measures the monitor against SNUADC directly.

Links to other clocks¶

Link	Clock	Against	Modes	Rate	Corrected every	Status
Solar8000 numerics against SNUADC	Solar8000 clock	SNUADC sample clock	all	0 s/h median (p10–p90 about ±0.5 s/h)	—	measured

Studies¶

Study	Date	Status	Summary
The SNUADC clock through the Solar8000 numerics, whole release	2026-10-19	current	On the SNUADC's own sample count, the delay from the waveform to the PC-stamped Solar8000 heart rate and mean arterial pressure ramps at the SNUADC's drift against the PC, measured without its stamps or resets. In recordings with whole reset intervals it agrees with them (−63 ppm; median difference +1.5 ppm, 581 recordings). It is too noisy per recording, and in recordings under about 4 h its rate is biased toward zero, so it cannot yet speak for recordings without resets.

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