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.

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.

Edge-lit seven segment display

IMG_1386-e1557372588487

Debra over at Geek Mom Projects posted detailed instructions of how to build this edge-lit seven segment clocks:

This build combines small dozens of small laser-cut acrylic pieces which fit together with very tight tolerances. It uses skinny (4mm wide) LED strips which must be soldered, bent, and then slotted in between those acrylic pieces. When assembling the parts you must be willing to force pieces into place, even though it feels like you are stressing the brittle acrylic. You must also be willing to remove and re-seat said pieces and LED strips when it turns out they *can’t* actually be forced into place. At some point during the assembly there is a strong likelihood that you will have to remove everything and re-solder your LED strip when you realize that forcing everything into place broke one of the wires away from your LED strip or created a short circuit.

See the full post on Geek Mom Projects blog.

Check out the video after the break.

Edge-lit seven segment display

IMG_1386-e1557372588487

Debra over at Geek Mom Projects posted detailed instructions of how to build this edge-lit seven segment clocks:

This build combines small dozens of small laser-cut acrylic pieces which fit together with very tight tolerances. It uses skinny (4mm wide) LED strips which must be soldered, bent, and then slotted in between those acrylic pieces. When assembling the parts you must be willing to force pieces into place, even though it feels like you are stressing the brittle acrylic. You must also be willing to remove and re-seat said pieces and LED strips when it turns out they *can’t* actually be forced into place. At some point during the assembly there is a strong likelihood that you will have to remove everything and re-solder your LED strip when you realize that forcing everything into place broke one of the wires away from your LED strip or created a short circuit.

See the full post on Geek Mom Projects blog.

Check out the video after the break.

PocketPi MK2

img_20190518_140600 A smaller thinner PocketPi from Facelesstech:

Thinner with a simpler design but packing the same feature as before. At its heart is a raspberry pi zero W with a 3.5″ screen 480×320. It has all the GPIO pins available what aren’t being used by the screen. Its powered by a 2500mAh battery and has one full sized usb port. Its controlled by a bluetooth keyboard with trackpad

More details on Facelesstech blog.

Check out the video after the break.

App note: Eye safety for proximity sensing using infrared light-emitting diodes

an_renesas_AN1737

A guide to human eye safety for designers of consumer products, app note from Renesas. Link here (PDF)

Active Proximity Sensing for Consumer products requires the use of a light-emitting component to illuminate the target object to be detected at some distance from the sensor. Typically, product designers do not want the illumination to interfere with the other functions of the product, or to distract the user during normal use. Therefore, Infrared Light-emitting Diodes (IR-LEDs) are used as the light-emitting components for proximity sensing. To further reduce the user awareness of the proximity function, the IR-LED and the proximity sensor are located under heavily tinted – but, infrared-transmitting – glass. While remaining unaware of any illuminating light source, the consumer indeed is exposed to low-levels of infrared radiation. All consumer products that emit light radiation – whether visible, ultraviolet, or infrared – must adhere to international standards that specify exposure limits for human eye safety.

App note: Basics on decoupling

an_avx_dcplbsc

See AVX technical note on how capacitors filter out transients in high speed digital circuits. Link here (PDF)

This paper discusses the characteristics of multilayer ceramic capacitors in decoupling applications and compares their performance with other types of decoupling capacitors. A special high-frequency test circuit is described and the results obtained using various types of capacitors are shown.