App note: Application of optical sensors – Transmissive

ap_optical_sensor_transmissive

Optical sensor basics and its considering factors of these type of contactless switches, learn more from Vishay’s app note on transmissive optical sensor.

These sensors integrate an infrared emitter and photo detector in a single package. The most common types of optical sensors are transmissive and reflective sensors. Both types detect the presence of an object without any mechanical or electrical contact. The output signal of the sensor is used to control various functions of an application

Transmissive sensors, also called interrupter sensors, incorporate an infrared emitter and photo detector that face
each other as shown in fig. 1. When an object is located between the emitter and detector in the sensing path, it interrupts or breaks the optical beam of the emitter. The light energy reaching the detector changes. This change in light energy or photo current is used to affect an event in the application.

Nooelec RTL-SDR giveaway at AmateurRadio.com

nooelec-nesdr-mini

AmateurRadio.com has teamed up with Nooelec.com to give away RTL-SDR packages to 10 hams. To be eligible to enter the competition, you must be a registered amateur radio operator, and you must comment on the competition page. The prizes are: Two (2) Complete HF sets including NESDR Mini receiver and accessories; Two (2) Complete Touch SDR sets including the NESDR Nano receiver and accesories; Three (3)bNESDR Mini receivers; and Three (3)bNESDR Nano receivers.

The competition runs until the 11th of December.

Remember, only comments on the AmateurRadio.com competition page are eligible for the contest, not those posted here.

Via RTL-SDR.com.

Free PCB coupon via Facebook to 2 random commenters

Dp-qfp-proto-v2

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. More PCBs via Twitter on Tuesday and the blog every Sunday.

Don’t forget there’s free PCBs three times every week:

Continue reading “Free PCB coupon via Facebook to 2 random commenters”

Week in (p)review December 06, 2013

exercise8_tilt_W600

Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon.

Coming up:

  • Free PCBs via Facebook on Friday
  • App notes on the weekend
  • Free PCB Sunday
  • Free PCBs via Twitter on Tuesday
  • Weekly roundup and preview every Friday

Telepresence robot using Microchip PIC16F1829 and Atmel AVR ATmega168 I2C smart DC motor controller microcontroller – Part 2

motor_cnt10

Ronald of ermicroblog writes:

The I2C (read as I square C) smart DC motor controller is designed using the Atmel 8-bit AVR Atmega168 microcontroller and configured to act as the I2C slave device where it could be controlled by other microcontroller or microprocessor through the I2C SDA (serial data) and SCL (serial clock) interface. In the first part we have accomplished a basic DC motor controller tasks i.e. differential steering and speed control using pulse width modulation (PWM). In this second part article I will put all the features described in Building the I2C Smart DC Motor Controller with Atmel AVR Microcontroller article – Part 1, this mean we will adding more features to the I2C smart DC motor controller firmware which include wheel rotation and servo control.

A digitally controlled dual tracking power supply — II

ps

Kerry D. Wong writes:

In my previous post, I showed my design of a dual tracking ±30V linear power supply. My goal was to use the transformer (28V+28V, center tapped) from an old Deltron W127G open-frame power supply and build a lab supply that can be digitally adjusted in both constant voltage and constant current modes. I also wanted each of the channels to be able to deliver up to 10 Amps of current so that I could fully utilize the 540VA transfomer from the W127G.

Turnigy 9X review – 9 Channel RC transmitter

transmitter180x270

Oscar Liang did a review of the Turnigy 9X RC transmitter:

The Turnigy 9X is one of the best RC transmitters out there at the moment for it’s price. For $60, you’ll get a 9 channel transmitter (8 usable), a receiver and a bind plug, but with no battery. I have been using this transmitter for over 3 months now, so I decided to share some of my opinions about this product.

GIVEAWAY: The Whistled, a sound controlled relay

PCB_only

Mathieu Stephan over at Limpkin wants to giveaway three whistled platforms (assembled PCB).  The whistled allows you to control one device by simply whistling two musical notes.

He’ll give these away to 3 random commenters, just leave a comment on this post.

For more information visit the project’s site -Limpkin.   It’s also up on Tindie.

GRCon13 video: Some More of Your RFz Are Belong to Me


At the recent GRCon2013, SDR guru Balint Seeber delivered this presentation on using GNU Radio to create new blocks and prototype flowgraphs relating to FasTrak RFID (used in traffic toll collection system), MUltiple SIgnal Classification (MUSIC) Direction Finding, RADAR Detection and Multi-channel Decodings.

SLENDUINO development board based on PIC12F683

board

Here’s a SLENDUINO development board based on PIC12F683 by C/D:

The idea of this project was born from the necessity of create projects focused to mobile; therefore PIC12F683-I/SN was almost immediately our first choice for the features of this microcontroller.

Files available on Github.

#FreePCB via Twitter to 2 random RTs

XT-IDE Adapter

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.

TI Ez430 Chronos watch – Getting started on custom firmwares

ez40_chronos_watch_black_friday_deal_thanksgiving

TI Ez430 Chronos watch – Getting started on custom firmwares:

Elpaso, from the 43oh Forums has written a nice tutorial on how to get started on the Ez430 Chronos watch with what is out there currently. He covers the watch, the control center, wireless updates and custom firmwares.

Via 43oh.

Relay control board on DP5031 PCB

RB01-brd

Tom writes:

Here’s a breakout board for those Songle SRD series relays that are so cheap on Ebay. It fits nicely on the Dangerous Prototypes standard PCB size DP5031.
Electromechanical relays are generally employ small signals to switch much higher voltages and currents. As a result, a nice big gap is required to insulate between the signal and load sides. It’s often a good idea to hive relays off to a separate board.

Via the project log forum.