US 12,105,167 B1
Buried utility locator auto-tuning apparatus and methods
Stephanie M. Bench, Sandersville, GA (US); Mark S. Olsson, La Jolla, CA (US); and Jan Soukup, San Diego, CA (US)
Assigned to SeeScan, Inc., San Diego, CA (US)
Filed by SeeScan, Inc., San Diego, CA (US)
Filed on Apr. 14, 2023, as Appl. No. 18/135,002.
Application 18/135,002 is a continuation of application No. 17/540,231, filed on Dec. 2, 2021, granted, now 11,635,479.
Application 17/540,231 is a continuation of application No. 16/921,775, filed on Jul. 6, 2020, granted, now 11,243,278, issued on Feb. 8, 2022.
Claims priority of provisional application 62/870,443, filed on Jul. 3, 2019.
Int. Cl. G01R 33/36 (2006.01); G01V 3/10 (2006.01); G01V 3/17 (2006.01)
CPC G01R 33/3628 (2013.01) [G01R 33/3678 (2013.01); G01V 3/10 (2013.01); G01V 3/17 (2013.01)] 15 Claims
OG exemplary drawing
 
1. 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.