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 […]
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 […]
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 […]
Following from the last post, I have been looking at the Raspberry Pi power supply and powering a USB external hard drive (HDD). I also changed from the 850mA Motorola phone charger to a 2 Amp 12V/5V supply (just connected the 5V) that was left over from a dead DVR. […]
To feed power directly to the Raspberry-Pi board without using the micro-USB connector, I soldered 2 wires directly to the back of the circuit board. The connection leaves the fuse and reverse-polarity protection diode in circuit. A couple of small holes drilled into the side of the case to form […]
I have recently updated the RC LED flasher controller to simplify the flash pattern programming slightly. Originally you needed a LED connected to channel 6 to indicate the pattern count. The small on-board status LED now provides the indication as well as channel 6; which is still useful when the […]
We have just done another test of the lost model tracker transmitter and the new yagi antenna. To make it interesting, a night test; in the dark. Waterproof the tracker transmitter I armed a transmitter using the servo tester, put it in a piece of bubble wrap and into a […]
You may have noticed that I’ve changed the main blog page to display excerpts rather than full posts. This was done mainly to reduce the download size and help speed up the page load time. To view the page with full posts that include pictures and sometimes quite a lot […]