March 2024

PIC Club notes for March 2024,   No meeting reports since October 2023.

MARCH 2024   Present: Andrew, Martin, Istvan, Alex, Lino, John Matthews 

Andrew showed a PCB developed for a water depth system. The probe is an enamelled wire and depth is measured by change of capacitance as probe is inserted into water. The change is linear and multiple probes can communicate back to a server using a TDMA protocol over 3 wires. Flow rate is measured by a sphere attached to a metal stem which bends proportionally to the water flow. 

Martin discussed a HW-586 Battery Capacity Tester Module he bought to measure capacity of li-ion batteries. The batteries are rated as 1100mah but using the tester showed only 800mah. 

Alex showed a free OCR feature in Windows in Tooltips, a link to a document showing how to read MOSFET datasheet and a project about building a home-brew quarter wave dipole antenna.

DIpole antenna

On the subject of radio communications, Istvan mentioned Android 15 phones are getting the ability to send text messages via satellite when there is no mobile coverage. Probably extra charges as well. 

Lino spoke about dangers of li-ion batteries and why they must be part of hand luggage instead of check-in. Also, fuel level in older generation  Mitsubishi car is measured with probes in a similar fashion to Andrew's method for water depth.