Comparing the MR9270S+ with my 3 previous reviews of the SG003A, SG004A and LB02 Process Calibrators and running the MR9270S+ through some accuracy tests.

Mr Signal MR9270S+
https://www.aliexpress.com/i/32771088...

Fnirsi SG-003A;
https://www.aliexpress.com/item/10050...

Fnirsi SG-004A
https://fnirsi.aliexpress.com/store/g...

Brightwin LB02
https://www.brightwinelectronics.com/...

0:00 Introduction
0:57 Tolerance Comparison
2:43 Physical Comparison to SG-004A
6:45 Accessing Calibration Constants
8:28 mV Sourcing Function
9:19 Voltage Sourcing Function
10:12 mA Sourcing Function
11:50 Ohms Sourcing Function
12:50 Ohms Measurement Function
14:41 mA Measurement Function
16:03 mV Measurement Function
17:04 Voltage Measurement Function
17:56 Polarity Measurement
19:16 Extra Tools Menu
21:29 Accuracy Specification Update
22:57 Kit Contents