WordPress becomes Very Slow

Solved Recently I found that for periods WordPress would become very slow, often taking more  than a minute to do anything. This seemed to begin for no apparent reason; fine one minute and dead the next. Then it would come right and be fine for a while. Because the site […]


smart 2 circuit relay module

Smart – 2 circuit relay module – updated

This is a low cost 2 channel smart relay module ideal for hobbyists and educational school projects as well as lighting and automation for home, commercial and industrial. It can be connected to provide power switching for Arduino, Raspberry Pi and other controllers. Use the standard configuration or reprogram it […]


Is the world a better place now than it was 30 years ago ?

30 years ago I was about 18 and had just started work doing an electrical apprenticeship with the local power authority. Life was really pretty easy; a 9 hour work day, regular pay, weekends and public holidays off. Things have changed a bit now with higher prices, never enough time […]


A-Open power supply repair

Computer power supply repair

This is from a low profile A-Open case that’s quite a few years old now but still in as-new condition and has been working well. The power supply sat on standby for some time and when it was needed did not go. Being a low profile case, it’s not possible […]


RC radio 2.4GHz reliability and options

2.4G band use increasing I have done a lot of surveying around my area, noting a big increase in 2.4G wifi over the last couple of years. What you can easily detect with a phone or laptop is only the tip of the iceberg. With a decent antenna or a […]


installing DOS from floppy

The Motorola 68HC11 Returns

A computer nightmare I needed to have another look at my original CPU_3A3 68HC11F1 module. I was assembling a few of these and needed to test them. Last time I did this, 5 or 6 years ago, I still had a laptop running Windows-98  and a bootloader program that was […]


1980 vintage home computer power supply repair

This is a off-line switchmode supply delivering +12V, -12V and +5V. The fault was that it wouldn’t work and a couple of capacitors on the mains input were in a bad way. Step one was to remove the faulty looking parts and clean the brown gunk off the board. Step […]

1980 vintage power supply repair

POE controller for outdoor camera or wireless AP

Raspberry Pi – POE – power over ethernet

I was considering using a Raspberry Pi for a weather station which got me thinking about remote mounting and how to power it. About two years ago I designed and built some POE controllers for camera housings and outdoor wireless access points. These pass Ethernet through, take the power off […]