My 2µF

I was having problems with the “led ring” boards. Their internal oscillators were not ticking with the same speed and required constant re-syncing. I tried to improve the situation by recalibrating by adjusting the OSCCAL registers. Recalibration can be done quite easily with an oscilloscope. Either assuming that the _delay_ms() routine is reasonably correct for [...]

robert Arduino., Electronics. AVR, calibration, DSO, frequency, hardware, oscillator

I’ve waited for 5 weeks for the 2nd batch of the 64-pixel RGB matrix controller boards. This time I ordered from MakePCB as I wanted to test another PCB manufacturer. Also I couldn’t get gold plated pads from GoldPhoenix for a reasonable price. As far as I can see right now, the boards are of [...]

robert Arduino., Electronics., PCBs 'n stuff. hardware, lead free, makepcb, PCB, RoHS

“FrOSCon is a two day conference on Free Software and Open Source, taking place for the third time on August, 23rd/24th 2008 at the Fachhochschule Bonn-Rhein-Sieg in Sankt Augustin near the cities of Bonn and Cologne.
“We are looking for contributions about current developments from the whole field of Free Software and Open Source., e.g.:”

Operating [...]

robert The Dump. hardware, open source

I was lucky :-)
It seems the guys at Sega just replaced the 470µF capacitors shown in the reference setup for the TDM2822M dual amplifier with 47µF ones. Other people have had problems with these too, so I just pulled them off and put standard 47µF 50V ones in as a replacement. I just had a [...]

robert Electronics., Fix me. computer archaeology, games, good old days, hardware, sega

Last time I turned it on, I didn’t get the usual boot-up sound of ‘Seeeeegaaaaa’.
There’s a little chip next to the earphone plug. I haven’t checked yet, but I suspect it’s some kind of amplifier. So I’ll warm up my good old TEKTRONIX 314 scope and go hunting for some sound waves, hoping the sound [...]

robert Electronics., Fix me. computer archaeology, games, good old days, hardware, sega