Controlling speakers with RADAR

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Speaker power controller made with a RADAR module from Scott Harden:

I just finished building a device that uses RADAR to toggle power to my speakers when it detects my hand waiving near them! I have some crummy old monitor speakers screwed to a shelf, and although their sound is decent the volume control knob (which also controls power) is small and far back on my work bench and inconvenient to keep reaching for. I decided to make a device which would easily let me turn the speakers on and off without having to touch anything. You could built a device to detect a hand waive in several different ways, but RADAR (RAdio Detection And Ranging) has got to be the coolest!

Project info at swharden.com.

Check out the video after the break.

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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.

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Process Automation: Relays and triacs

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Andy Brown designed and built this relays and triacs controller board that he could use to automate his homebrewing process:

The heaters, fridge and fans that control the temperature in my brew fridge need to be switched on and off and that’s what this board is designed to achieve.

As you can see from the diagram the main features of the board are:

  • Three relays for basic on/off switching. To solve one of the issues with the STC-1000 controller I will use 16A, name brand relays for maximum reliability.
  • A triac. This will give me the ability to do phase-angle ‘dimming’ control and will be used for proportional heater or fan control.
  • USB connectivity to the host PC via a USB-to-UART IC.

More details at andybrown.me.  Firmware source code available on github.

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Extend Eagle CAD tool with ULPs: Writing your first User language program

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Yahya Tawil posted a detailed how-to on writing ULP’s for Eagle CAD:

In this tutorial, you will learn how to write your first ULP in Eagle CAD to add a new capability to your CAD tool.
User Language Program (ULP) is a set of extensions for Eagle CAD users to either facilitate a routine job in an automated way or do a job that can’t be done without a ULP’s help. For example, the only way to import an image to your PCB design is by using the command import-bmp ULP. Auto-placement, exporting BOM, and renumbering parts in a schematic are all routine jobs with which ULP can help.

More details at allaboutcircuits.com.

Via the contact form.

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YouTube channel IoT view counter

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Kenneth Finnegan built this YouTube channel IoT view counter, inspired by Becky Stern’s IoT counter:

I’ve wanted an Internet connected read-out for some time now, inspired by the awesome shadow box IoT projects Becky Stern has been doing (weather, YouTube subscribers). I’m certainly not to the same level of packaging as her yet, but I’ve got a functional display working with a Hazzah and an eBay seven segment display module.

Project info at Kenneth’s blog.

Check out the video after the break.

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Dallas Semiconductor DS1284 die decap: A look at a 30 year old design

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Dallas Semiconductor DS1284 die decap from Electronupdate:

The Dallas Semiconductor DS1284 (and related DS1286 which integrated a battery and crystal in the same package) found lots of use in industrial control and test equipment.
30 years ago processor chips contained not much other than the processor. Utility functions such as real time clocks, non volatile ram and watchdogs were always external.
Dallas semiconductor was quite successful in creating some of these utility chips which put a number of functions into a single device. The company was eventually acquired by Maxim in 2001.

More details at Electronupdate blog.

Check out the video after the break.

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#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.

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App note: HT45F3630 power tool speed control switch application example

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All in one motor control MCU HT45F3630 from Holtek. Link here (PDF)

Aimed at the motor speed control product application area, HOLTEK has developed the HT45F3630, which is commonly used in electric drills, electric screwdrivers, lawn mowers and other similar product applications. This MCU provides a group of PWM high voltage and large current output pins which can directly drive Power MOS transistors to reduce their switching losses. Additionally, the device includes integrated over current protection and detection functions and an amplifier which allows the input signal to be amplified by 51 times, requiring a lower value current sense resistance value which will increase the overall efficiency and extend the operating time. When an over current event occurs, the PWM switching will be shut off by hardware to achieve immediate protection.

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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 http://ift.tt/2t46FA4