Devlog #01

I am making a precision 10V Standard based on LM399.

— Reference schematic —

I managed to make a schematic for the reference, gain stage and calibration resistors. The output can be calibrated by soldering required jumpers that connect trim resistors.
I want to achieve sub 5ppm stability, so the resistors for the gain stage must be precise and stable.

— Power supply —

Now I should focus on power supply. The heater will be powered from a separate source. Another important thing about building the PSU is isolation. It has to be isolated from mains quite well so leakage currents will not mess up the measurements. Capacitance between transformer windings is a problem.