This old circuit, from the 80s, was found in American documentation. The circuit uses dual gate FETs (MOSFETs) and has no data on the coils used.
Combining an Ultra-Low Power MCU with an 802.15.4 Radio, the SAM R30 Enables Long-Lasting Battery...
This comparator with two Texas Instruments operators was obtained in a company application manual....
August 2017 - Mouser Electronics already has the Connect One Pico WiReach ™ SMTS Pico modules...