App note: Ambient light sensor SFH5701

an_osram_sfh5701

App note from OSRAM on their ALS device SFH5701, its operation and application method. Link here (PDF)

The SFH5701 is a small, two-wire, linear output current ambient light sensor (ALS) with current amplifier and dark current compensation. The ALS is capable of resolving a wide range of ambient light levels (10 mlx – 10 klx) tailored to the spectral response of the human eye and operational from -40 °C to 100 °C.

from Dangerous Prototypes https://ift.tt/2G54sfa

Free PCB coupon via Facebook to 2 random commenters

BP

Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

from Dangerous Prototypes https://ift.tt/2E8WCic

Teensy 3.6 as standalone mediator between USB MIDI and Eurorack

DSC08219-600

Sebastian writes:

USB MIDI controllers (such as Launchpad Mini Mk II for example) are common and often quite low in cost.
To interface such a controller with a Eurorack synth system, often a host computer and a MIDI to CV interface might be used. The host computer would take USB MIDI data from the MIDI controller, perhaps store and manipulate that data in some way (e.g. a sequence), using a MIDI to CV converter to then control a Eurorack synth system.
It would be useful to use USB MIDI controllers with Eurorack synth systems without needing a computer and MIDI to CV interface in between the two.
Teensy 3.6 is a great microcontroller that can be programmed using the Arduino IDE. A very useful feature of the Teensy 3.6 is the USB host port.

See the full post on his blog here, Little-Scale.

Check out the video after the break.

from Dangerous Prototypes https://ift.tt/2PrcZsb

New 2.5D pen/laser ESP32 controller

20181128_204306

Bdring published a new build:

I have done several pen and laser machines lately, so I decided to create a custom PCB for Grbl_ESP32 for these types of machines. This is a small (70mm x 60mm) PCB with all the features a pen plotter or laser cutter/engraver would need.
These typically use stepper motors for the X and Y axes. On pen plotters, the Z axis is controlled by a servo or solenoid. On lasers you need an accurate PWM for laser power control.

Project info at Buildlog.Net blog and the library GitHub repository here. It’s also up on Tindie.

from Dangerous Prototypes https://ift.tt/2zIPzcH

#FreePCB via Twitter to 2 random RTs

BP

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week:

  • Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

from Dangerous Prototypes https://ift.tt/2RB31X2

DakBoard family calendar with Raspberry Pi Zero W and Read Only filesystem

DakBoard Family Calendar

Scott Hanselman made this DakBoard family calendar with Raspberry Pi Zero W and wrote a post on his blog detailing its assembly:

The implementation is simple genius. It’s a browser that starts up full screen (kiosk mode) and just sits there and updates occasionally. DakBoard provides the private webpage and tools to make that happen. You can certainly build this yourself with any number of open source tools. I chose DakBoard because it was simple, beautiful, and I was able to get the whole thing done in less than an hour. I’m sure I’ll spend many hours tweaking it through. There’s also the very popular MagicMIrror platform, so lots of choice and power in this space!

See the full post on his blog here.

from Dangerous Prototypes https://ift.tt/2QeQE6k

The OpenBrite Turbo controller for Vectrex

Vectrex Controller Prototype

Stephen Wylie blogged about his Turbo Vectrex controller build:

 The main impetus for this was to have a homebrew controller that actually featured an analog joystick, since there were few if any guides elaborating how to fashion one from an existing controller.  I acquired a couple Parallax 2-axis joysticks with breadboard mounting capability to do the trick.
The Vectrex comes with a game in its ROM — Asteroids — thus you can play without needing a cartridge.  However, with the traditional controller, this requires lots of button-mashing since it has no auto-fire feature.  Using a 555 timer, potentiometer, and clever values within an RC circuit, I have given it the ability to auto-fire.

See the full post on his blog here, GOSHtastic.

from Dangerous Prototypes https://ift.tt/2FXNfnY