Tektronix scopes do not specify an MSU (Measurement System Uncertainty) specification, but we do offer an ISO Guide to the Expression of Uncertainty in Measurement (GUM) with our Cal Certs. The coverage factor (k) is 2, with coverage probability of approximately 95 %. Uncertainty values are reported with the same units as the measured values. Statements of conformity to specifications account for uncertainty. Statements of conformity to specifications are made with less than 2% global false acceptance risk for each measurement result.
This information is specified directly from our Calibration certifications (Cal Cert). You should have received this calibration document when you first received the instrument.
If you want to reference our document that contains the specifications for the MSO5000B, I have linked the Performance verification manual below.
MSO5000B Specifications and Performance Verification: https://www.tek.com/en/oscilloscope/dpo70000-mso70000-manual/mso-dpo70000dx-mso-dpo70000c-dpo7000-c-mso5000-b-and-dpo5000
• MSO5000B Specs are on page 77 (PDF page 89)
I hope this helps!