Practical Electronics No 6 2024

Wi-Fi Time Source for GPS Clocks by Tim Blythman. The Raspberry Pi Pico W can be used as a substitute for GPS modules in existing time keeping designs, for when you can’t get a reliable GPS signal. It gets the time from an internet NTP server via Wi-Fi and is accurate to a fraction of a second.
Heart Rate Sensor Module by Jim Rowe. This design features an Analog Devices AD8232 heart rate monitor front-end IC which provides a low-cost way to monitor the operation of the heart via an Arduino MCU or similar.
Loudspeaker Test Jig by Phil Prosser. Use your PC’s sound card to measure loudspeaker performance, inductors, capacitors and complex impedances. With this Jig and appropriate software, measuring and tweaking crossovers, cabinets and speakers is easy.
Setting up and using Room EQ Wizard by Phil Prosser. This accompanying article for the Speaker Test Jig explains how to set up and use the freely-available Room EQ Wizard (REW) or Speaker Workshop software to help you design and tweak loudspeakers.