Size: about 50x50mm (size of condoms I have, could be a little larger if required)Layers: preferrably a single 2-layer PCB, for easier ordering at the usual suspects in ChinaConnections: debug UARTMicroUSB for charging the batterytemperature sensor connectortwo...
The PCB arrived and they look perfect, not that I had any doubt when ordering at a big Chinese manufacturer. And of course there are mistakes :/ The voltage regulator for USB power to the GPS chip U5 has the wrong footprint. I used a SOT-89-3 foot...
Requirements Easily found when misplacedBig enough to hold easily but not too big that it's cumbersomeShould have a battery compartment so that unskilled personnel can replace batteries without having to open up the housingRoom enough for the necessary...
I sent out the Headband Sensor Package Version 0.89 PCB's to OSH Park, Got three purple PCB's back, and they look great! The top and bottom of the boards look pretty good. I could have flipped the resistor silkscreen (the R1, R2 and R3),...
After a sinuous but exciting road, the Beta prototype came out nice, the entire device is amazingly small: I was able to design it to fit the 110x70mm aluminium enclosure I planned initially without renouncing to any of the sensors nor reducing the 1500mAh...
On my TI-89, one of the battery contacts on the PCB was heavily corroded and it took a good deal of time and heat to reflow solder to make a new pad. I did this to the V200 as a preventative measure too, but I guess I heated up the nearby fuse to where...
It's already out since July, but just to log the improvements:There's actually a lot to learn about kit-making: how to prevent beginners from messing up soldering a computer kit for the first time. So it was time for a revamp of the PiDP-8, putting in...
PCB Rev 1 are working and usable but there is room for BOM cost optimization. Current sale price could be 89 EUR, with extensive BOM optimization it could be lowered - hopefully. USB micro-B to USB mini changeFTDI USB connector is currently micro-B footprint...
The build of the module was pretty strait forward...with some complications. Except for one all footprints matched the parts I have. The LDO for VCC_USB was the wrong footprint, a SOT-89-3 should have been a SOT-223. I fixed this by soldering cables...
With the compass functionality tested on a breadboard, the next step is to transfer it to a universal prototyping board, adding a status display and IO expansion ports to drive a LED ring that simulates the horizon. For the board, I am going to use the...
I wanted to connect replacement LCD to the original LCD connector, with no "ugly hacks" like interfacing with VGA connector and other workarounds. The original LCD used 9-bit TTL RGB interface (3 pins for red, 3 pins for green, 3 pins for red), which...
Microscope slides, 3-D printed parts and the finished test-tube-shaped micro reaction chamber. 2-component 5-minutes epoxy resin adhesive has been used to glue the microscope slides and nipples in place:Leakage test (pass):Populated PCB:Reaction chamber...
I promised this log for several times and now it is finally here. Let's start with how a rising edge looks.RisetimeThe orange and light blue ones were measured using commercial devices, the Agilent 86100C and LeCroy WaveRunner (this one was already mentioned...
Ok, sorry about the clickbait title; who can resist the promise of LEDs? I promise a photo of a lit LED in this log, so you don't go home empty handed. This log is a quick one to introduce an intriguing potential alternative to coin cells. I have...
See Update BelowContext being more that of the puzzle of cases not one case "to rule them all," but I digress. The past week I've been going through a few catalogs to find an enclosure for D-DAQ's mainboard. Previously, the PCB's form factor was based...