Buried utility locator auto-tuning apparatus and methods

A buried utility locator, comprising:

• One or more omnidirectional magnetic antenna nodes;
• And a receiver circuit operatively coupled to the omnidirectional antenna nodes, comprising:
• an auto-tuning electronic circuit module for generating tuned output signals, comprising:
• a tunable resonant electronic circuit element comprising a first capacitor and an inductor in series driven by an input signal which is a square wave at a resonant frequency for providing a tuned output signal;
• a capacitive voltage divider circuit coupled between the first capacitor and inductor;
• a tuning array element circuit coupled between capacitors of the capacitive divider circuit, the tuning array element including a plurality of tuning capacitors and mated switches;
• and
• a control element including a sensing element for measuring output signal strength and a processing element for comparing previous output signal strength values stored in a non-transitory memory element to a current signal strength value and providing a corresponding control signal to control actuation of the mated switches.