Open-source, Printed Dual-Loop RF Magnetic Field Probe for the RF Coil Lab

Motivation: Decoupled dual-loop RF probes are common tools in the RF coil lab, but the traditional design requires skill and experience to build well. They are also delicate because they are made using semi-rigid or hand-formable coaxial cable. Goal(s): To develop a tough, reliable dual-loop probe design that can be mass-produced inexpensively. Approach: We used two overlapped shielded loops fabricated with multilayer printed circuit board technology. Design files are published under an open source license. Results: The printed probe achieves the required levels of durability and high isolation (better than 50 dB up to 500 MHz). Impact: Dual-loop probes are frequently used for RF coil measurements but they are not readily available commercially. This work allows new and established labs to obtain these probes with minimal effort. The design files are available on Github.