Thinking about just getting this one. It's $8 and the AD584L. They also measure with a 6 digit calibrated multimeter, at all four voltages: 2.5, 5, 7.5 & 10V. And they share their results on the bottom on a label. All you have to do is dial in your meter to match their numbers.
Beware, not all meters can be calibration adjusted that easily. They might need specific voltages and all ranges done, not just individual.
Thanks. I should of known it wouldn't be simple! In fact, I am looking at the owners manual for the Fluke 8050A meter I am getting in a few days. Looking at the calibration section. To calibrate DC voltage measurements, it requires it to be calibrated in four stages. You need to supply it a different voltage value each stage, adjusting 1 of four resisters each stage.
From the instruction manual:
4-44 DC Calibration
4-45 Use the following procedure to perform a DC Calibration:
1. Connect the DMM Calibrator to the 8050A as follows: H1 to the V/kohm/s input connector and LO to the COMMON input connector.
2. Select the DC V function on the 8050A
3. Turn on the DMM Calibrator
4. For each step in Table 4-8, select the range shown, and adjust the DMM Calibrator for the required 8050A voltage input level, then adjust the indicated component to the display limits.
Table 4-8 DC Calibration:
Step 1: Range 2V, Voltage INput: +1.9000V, Adjust R11, Display Limits: +1.9000 exactly
Step 2: Range 200mv, Voltage Input: +190.00 mv, Adjust R12, Display Limits: +190.00 exactly
Step 3: Range 200v, Voltage Input: +190.00v, Adjust R5, Display Limits: +190.00 exactly
Step 4: Range 1000v dc, Voltage Input: 1000.0v, Adjust R6, Display Limits: +1000.0 exactly