The inside of an EEVBlog 121GW 4 4/5 digit multimeter. Just to see how it's built.
The PCB, both sides:
Housing and boot:
Links:
.
I'm going to do a few measurements - to try out some of the specifics of the meter.
A Digilent / TI Analog Shield and some resistors act as test devices. Keithley DMM6500 as reference for measurements.
+2.5 V reference. The two meters probe at exact the same point.
Goal is to view how close the measurements are, not how good the reference (LM4128) is.
I can't use the two meters together because they 'd influence in this case.
I've left the resistor part the same for each measurement and swapped the leads at the meter side.
10 K
1K8
470R
in VA mode, where the current and voltage is measured and the VA (this is DC, so equals W) is derived.
The 2nd display flashes between V and A.
in VA mode, where the current and voltage is measured and the VA (this is DC, so equals W) is derived.
The 2nd display flashes between V and A.
