This is a section of an analogue multi-meter circuit diagram. I am interested in this section in particular as I am unable to determine the function of the 220 pF capacitor C1. It is connected in parallel to 800 Ω R6 and 8.2 kΩ R32. They are then in turn connected to a small transformer and then to the need movement. The supply is 10 V @ 50 Hz. What function does the capacitor serve? I’ve used an oscilloscope and confirmed it does not have any smoothing affect.

 

hi 8,
Please post a larger view area of the circuit so that we can where and what its connecting too.
E

 

Hope you can see this ok

 

AC frequency compensation

 

AC frequency compensation

Seconded.

 

This is a section of an analogue multi-meter circuit diagram. I am interested in this section in particular as I am unable to determine the function of the 220 pF capacitor C1. It is connected in parallel to 800 Ω R6 and 8.2 kΩ R32. They are then in turn connected to a small transformer and then to the need movement. The supply is 10 V @ 50 Hz. What function does the capacitor serve? I’ve used an oscilloscope and confirmed it does not have any smoothing affect.

Think in simpler terms. What waveform does a transformer work at? A/C of course. What does a capacitor do with an A/C waveform, that it does not do with a D/C waveform? It passes an A/C waveform, while also controlling the current. It blocks a D/C waveform, so the cap is an A/C bypass, and hence a 'compensator' for the A/C waveform.