I want to know how to determine the output frequency of an FM receiver given the carrier frequency and the modulator frequency.

This receiver is the one I made. The only way I can determine frequency is to keep switching capacitors in the tank circuit until I pick up a station that tells me the frequency. There are no labels to look at and I dont have a multimeter with the frequency function on it. I have recently bought a digital multimeter that can measure voltage, resistance, transistor hfe, and current.