Dit is mijn professionele activiteit. Bij Opticon ontwikkel ik aan barcode-apparatuur en elektronische displaysystemen. Ik vind het daarbij erg leuk om ook in priv├ętijd aan projectjes te werken.

Ceramic capacitors: why you should not assume "X5R is good enough"

In my original article about the Geekworm Raspberry Pi UPS HAT board a modification was described to adress an issue with this board: after only a short interruption of the external power, the board will not resume recharging the battery anymore, unless the pushbutton is pressed, which will also switch the Raspberry Pi off.

This article proposes a relatively simple modification, which may make the UPS HAT board more useful in your application.

Generally speaking, the modification should enable the Raspberry Pi to continue operation indefinitely, despite power interruptions of up to several hours. However, after an even longer power interruption, manual intervention may still be necessary to restart it.

Mijn compacte PC-luidsprekers produceren niet al te lage bassen. Met een oude subwooferbox, een versterkermodule en de hier beschreven schakeling heb ik een actieve subwoofer gemaakt.

UPS (Uninteruptible Power Supply) solutions for the Raspberry Pi are available, but generally at rather high prices in comparison to that of the Pi itself. Some time ago, the Geekworm Raspi UPS HAT Board became available on Chinese webshops such as Banggood and DealExtreme. It appears an interesting deal, but it depends on your usage scenario whether it is suitable as an UPS.

I evaluated the functionality of this product and reverse engineered it. This article provides information such as a circuit drawing, and suggestions for modification.

Dit artikel geeft een overzicht van toeleveranciers (componenten, PCB's en meer) die ik kan aanbevelen.