Mike, it's the switchery that will be the hardest, best to view it in terms of a Wheatstone bridge, look at the one here:
https://www.electronics-tutorials.ws/blo...ridge.html
First, resistance: Substitute R1 and R2 with the main pot track and make point "C" the wiper, call R4 R range and call R3 Rx, now replace the battery with an AC sinewave source (your transformers secondary) then connect the 'phones across Vout (between points "C" and "D") That's the set up for the unknown R measurement (Rx).
Next, capacitance (non electrolytic): As above but replace R4 with a capacitor, call that capacitor C range, replace R3 with a capacitor, call that capacitor Cx, that's the set up for the unknown C measurement (Cx).
Next, capacitance (electrolytic): as above but replace R4 with a capacitor in series with the PF rheostat, that's the set up for measuring Cx and the power factor at the test frequency.
Lawrence.
https://www.electronics-tutorials.ws/blo...ridge.html
First, resistance: Substitute R1 and R2 with the main pot track and make point "C" the wiper, call R4 R range and call R3 Rx, now replace the battery with an AC sinewave source (your transformers secondary) then connect the 'phones across Vout (between points "C" and "D") That's the set up for the unknown R measurement (Rx).
Next, capacitance (non electrolytic): As above but replace R4 with a capacitor, call that capacitor C range, replace R3 with a capacitor, call that capacitor Cx, that's the set up for the unknown C measurement (Cx).
Next, capacitance (electrolytic): as above but replace R4 with a capacitor in series with the PF rheostat, that's the set up for measuring Cx and the power factor at the test frequency.
Lawrence.
