I had a NOS Staco variable transformer for while. Finally I was able to put things together in a semi open wood cabinet.

I recently built a pair of chokes for my future headphone amp. They are designed to be 25H at 70mA . I built an excel calculator to calculate chokes:

Here are chokes:

It is now when I need the Variac. I am trying to figure out the best way to measure these chokes and see how close is their inductance to the designed value…

Using PSUD2 to simulate the power supply it shows a 60mA dc and 0.4mApp. The ideal way to measure the inductance is to simulate the conditions that the choke is working in reality.  To be continued…