I am interested in the comparison of capacitors and inductors.
I can very precisely make a push pull driver with opamps and thermally matched resistors. This can be coupled with two foil capacitors and the drift is the tempco of the capacitor. Its reactance will have a voltage drop proportionalto temp. Its approximately 160ppm/degree c.
The capacitor can be made large to lower the effect of its reactance drop, however i am also very concerned about dc leakage, and dc leakage over temperature. This forces me to use foil capacitors, which are rather large past 10uf or so.
I am interested in taking ppm measurements to make a choice.
Should i focus on measuring steel laminated ones to get some sort of idea?
My measurements on inductors lead me to believe they have a tempco of approximately 600ppm/degree c. This is worse then capacitors, so the reactance would need to be four times lower to match the performance of capacitors.
Anyone got any numbers? Otherwise i need to make a tempco box.
In that case, any suggestions on a good balun to test? Will the materials used in a common mains transformer be the same as an audio transformer? The type of steel?
Also it looks like i need to meausure both dc resistance drift and inductance drift and correlate them