3D printed stirling engine gas burner and flywheel

Stirling Engine

The 3D printed Stirling Engine with its new gas burner and heavier flywheel from Do It Yourself Gadgets:

Take a look at my upgraded Stirling Engine with its new gas burner and flywheel!
If you take a look at my previous post you’ll see how I built a 3D printed holder for my Stirling Engine kit. Since I needed a constant heat source I added a small gas burner salvaged from an old BBQ lighter and attached it to the engine.

See the full post on Do It Yourself Gadgets blog.

Check out the video after the break.

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Free PCB coupon via Facebook to 2 random commenters

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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/2KzcOJG

LoraDunchy Arduino Nano pin-compatibile LoRa module with power management

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Mare writes:

Lora board with Arduino nano compatibile pinout and simple battery management
Small board with arduino nano compatibile pinout with power management and Murata ABZ LoRa module with STM32L0 microcontroller
Features:
-LoRa module: Murata ABZ
-Single cell LiPo cell charger on-board with charging signal internally connected to PA11 (via jumper)
-Buck/Boost switching power supply for delivering stable 3,3V regardless of the batterz voltage
-Battery fuel gauge on-board to control the real status of the battery

See the full post on Mare & Gal Electronics blog and the GitHub repository here.

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A touch numeric keyboard for Arduino or Teensy

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Giovanni Carrera blogged about his touch numeric keyboard for Arduino or Teensy:

Very often, for our programs, we need a system to set parameters, usually of a numerical type. A 4×4 keyboard requires some space and then we also need a display. Here is the idea of using a touchscreen display to do both. I have then written the GetNum function that allows you to print a prompt message and to type an integer number. To test this function I wrote a simple analog data logger program that required two parameters, the first is the sampling period and the second the number of samples. In this example the number of channels to be scanned is set to three, but the program can be modified to request a third parameter with the number of channels.

See the full post on ArduPicLab blog.

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

Ethernet Relay board

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Boris Landoni from Open Electronics writes about a new open source project Ethernet Relay board:

The project we are introducing in this article wants on to take on that task by creating, through dedicated connections, the possibility to remotely control your entrance gate, your fish tank, the garden lights, the watering system and so on, using numerous examples. It is an ethernet-controlled relay board, which can be used as an actuator to directly control 220 V loads, to command 0V ÷ 5V digital signals or to read the status of digital or analog inputs; everything can be done remotely by using an Internet capable LAN.

Full details at open-electronics.org.

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EEPROM rotation for ESP8266 and ESP32

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Xose Pérez over at Tinkerman writes:

The Arduino Core for ESP8266 and ESP32 uses one SPI flash memory sector to emulate an EEPROM. When you initialize the EEPROM object (calling begin) it reads the contents of the sector into a memory buffer. Reading a writing is done over that in-memory buffer. Whenever you call commit it write the contents back to the flash sector.
Due to the nature of this flash memory (NOR) a full sector erase must be done prior to write any new data. If a power failure (intended or not) happens during this process the sector data is lost.
Also, writing data to a NOR memory can be done byte by byte but only to change a 1 to a 0. The only way to turn 0s to 1s is to perform a sector erase which turns all memory positions in that sector to 1. But sector erasing must be done in full sectors, thus wearing out the flash memory faster.

How can we overcome these problems?

Full details at tinkerman.cat.

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TRL measurements with homemade VNA and open source software

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Henrik Forstén writes:

I have been using the OSH Park’s 4 layer process a lot on my own projects. It has FR408 substrate that has better controlled permittivity and lower losses than ordinary FR-4 that other low cost PCB manufacturers use. In my opinion currently it is the best low cost process for making RF PCBs. My previous boards have worked pretty well, but I decided to make a test board that I can use to characterize the process better.
In the above picture is the test board that I made. It has two 50 ohm microstrip lines of different length, one open microstrip line, one microstrip line terminated with 50 ohm resistor and line with 0402 footprint that I populated with a 1 nF capacitor. I’m using this same type of capacitor as a general DC blocking capacitor in my VNA so I’m interested in finding out how it performs at high frequencies.

See the full post on Henrik’s blog.

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#FreePCB via Twitter to 2 random RTs

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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/2IvsQlZ

Amiga 500 power supply build

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A how-to on building an Amiga 500 power supply from Inkoo Vintage Computing:

The power supply of my Amiga 500 is a bit unreliable. I’ve had some issues with the machine where the PSU could be the culprit, so I thought that it would be better to get a new power supply. There are used Amiga 500 power supplies occasionally available on online auctions, and there are also unused (but probably quite old) power supplies available on some online retailers. The issue with these 20-30 year old power supplies is that the capacitors are starting to dry. This can be a fire hazard, as old capacitors may even explode (this has happened to the PSU of my old IBM XT, it was not a pleasant experience). So in order to get safe and reliable operation from an old PSU, the capacitors should be replaced.

More details on Inkoo Vintage Computing homepage.

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Free PCB Sunday: Pick your PCB

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We go through a lot of prototype PCBs, and end up with lots of extras that we’ll never use. Every Sunday we give away a few PCBs from one of our past or future projects, or a related prototype. Our PCBs are made through Seeed Studio’s Fusion board service. This week two random commenters will get a coupon code for the free PCB drawer tomorrow morning. Pick your own PCB. You get unlimited free PCBs now – finish one and we’ll send you another! Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Be sure to use a real e-mail in the address field so we can contact you with the coupon.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.
  • PCBs are scrap and have no value, due to limited supply it is not possible to replace a board lost in the post

Be the first to comment, subscribe to the RSS feed.

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