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Building a GBA LiPo voltage regulator and charger

Posted on Thursday, June 21st, 2018 in DIY by DP | 1 Comment

IMG_4672

Alex published a new build:

I saw a post where someone fitted a 2000mAh LiPo battery to their GBA, they had do to some modifications to the GBA battery compartment to fit it all. By using a LiPo battery instead of the AA’s, it would save us about 20 grams, while not a lot, ever gram does count and you can tell the difference plus since the LiPo has a higher voltage, it has a higher energy density, so it should give us longer play time than the AA’s. So I decided I would do the same mod and I might make a little voltage regulator and charging board to go along with it.

See the full post on insideGadgets project page.

A software only solution to the vexing Beagle Bone Black PHY issue

Posted on Thursday, June 21st, 2018 in hacks, software by DP | No Comments

Maker:0x4c,Date:2017-12-4,Ver:4,Lens:Kan03,Act:Lar01,E-Y

Josh Levine has a nice write-up about a software only workaround for the Beagle Bone Black PHY issue:

Sometimes the Ethernet port on a Beagle Bone Black does not work on power up. It takes either a physical reset button press or a power cycle to fix it. This problem affects all BBB’s and until now could only be solved with hardware hacks.

The final official word from TI on this problem:
“There is no solution for this on the BB Black“

Full details at josh.com.

Tutorial: Setting up a low cost QRP (FT8, JT9, WSPR etc) monitoring station with an RTL-SDR v3 and Raspberry pi 3

Posted on Tuesday, June 19th, 2018 in R-Pi, RF, tutorials by DP | No Comments

qrp_ft8_jt965_wspr_2

A detailed tutorial on how to set up a cheap QRP monitoring station using an RTL-SDR V3 and a Raspberry Pi 3 from rtl-sdr.com

This tutorial is inspired by dg0opk’s videos and blog post on monitoring QRP with single board computers. We’ll show you how to set up a super cheap QRP monitoring station using an RTL-SDR V3 and a Raspberry Pi 3. The total cost should be about US $56 ($21 for the RTL-SDR V3, and $35 for the Pi 3).
With this setup you’ll be able to continuously monitor multiple modes within the same band simultaneously (e.g. monitor 20 meter FT8, JT65+JT9 and WSPR all on one dongle at the same time). The method for creating multiple channels in Linux may also be useful for other applications. If you happen to have an upconverter or a better SDR to dedicate to monitoring such as an SDRplay or an Airspy HF+, then this can substitute for the RTL-SDR V3 as well.

More details at rtl-sdr.com.

RobotX is open source

Posted on Tuesday, June 19th, 2018 in open source, robotics by DP | 3 Comments

ROBOTX

James Bruton writes, “I’ve decided to open-source RobotX so anyone can have a go. I also made some extra foot sensors for the robot in the video below. You can get the CAD and code from my Github.”

See the full post on XRobots blog.

Check out the video after break. (more…)

Sega System 16 security reverse engineering

Posted on Tuesday, June 19th, 2018 in reversed by DP | No Comments

sega-programmer

Reverse engineering of Sega’s System 16 Hitachi FD1089 cpu security module by Eduardo Cruz:

I’m glad to announce the successful reverse engineering of Sega’s System 16 cpu security modules. This development will enable collectors worldwide preserving hardware unmodified, and stop the general discarding of Hitachi FD modules.
The project is right now involving external testers so expect further details and full disclosure over the coming weeks.

Further details on Arcade Hacker blog.

Check out the video after the break. (more…)

#FreePCB via Twitter to 2 random RTs

Posted on Tuesday, June 19th, 2018 in Free PCBs by DP | No Comments

IRToy-600x369

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.

Neopixel clock, v2

Posted on Monday, June 18th, 2018 in Arduino, clock by DP | No Comments

Neopixel Clock

David Zweben published a project writeup showing how he built a Neopixel clock powered by an Arduino Pro Mini clone and a real time clock module:

After building my first Neopixel Clock, I decided I needed one for myself. There was no way I was going to solder 90 lengths of wire onto 180 tiny pads again, though, so I knew I needed to design a custom PCB. This necessitated a redesign of the entire clock, focused around making it as easy as possible to assemble.

Project info at zweben.org.

Check out the video after the break. (more…)

Game of Life on a Raspberry Pi (and a LED board) in Haskell

Posted on Monday, June 18th, 2018 in LEDs, R-Pi by DP | No Comments

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Trandi published a Game of Life on a Raspberry Pi in Haskell project, that is available on Github:

This is a quick post about, re-purposing my Raspberry Pi + Peggy2 art installation, which already re-purposes a 8-9 years old Peggy2 LED board, to play Conway’s Game of Life.

More details on Robotics /Electronics /Physical Computing blog.

Check out the video after the break. (more…)

Free PCB Sunday: Pick your PCB

Posted on Sunday, June 17th, 2018 in Free PCBs by DP | 7 Comments

BP-600x373

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:

(more…)

App note: Trends in integrated circuits that affect ESD protection requirements

Posted on Sunday, June 17th, 2018 in app notes by DP | No Comments

an_on_AND8309-D

A quick lookup on the ESD protection evolution of ICs in this app note from ON Semiconductor. Link here (PDF)

The stunning progress in integrated circuit capability over the last 40 years is most succinctly expressed by Moore’s Law; “Every 2 years the number of transistors that can be economically manufactured in an integrated circuit will double”. The secret to this success has been the shrinking of integrated circuit feature sizes in all three dimensions. To maintain circuit reliability with the smaller dimensions the operating voltage of integrated circuits has been steadily declining. This trend will continue in the future, as documented in the International Technology Roadmap for Semiconductors. As the working voltage for integrated circuits decreases the voltage at which circuit damage can occur also decreases.

The move to smaller geometries has also prompted fundamental changes in IC technologies that have had an adverse effect on the intrinsic ability of the technologies to survive ESD stress. A prime example is the evolution of nMOS transistors in CMOS technologies.

App note: Circuit configuration options for TVS diodes

Posted on Sunday, June 17th, 2018 in app notes by DP | No Comments

an_on_AND8231-D

Different TVS configuration usage app note from ON Semiconductor. Link here (PDF)

Transient Voltage Suppression (TVS) protection is important because EMI and ESD can disturb the operation of the system, produce permanent damage or cause latent damage that will eventually cause a failure. Avalanche TVS diodes and diode arrays are available in a number of different circuit configurations to protect electronic circuits from surge voltages. This document will analyze the attributes and trade-offs of different circuit configurations created with avalanche TVS and diode array protection devices.

Free PCB coupon via Facebook to 2 random commenters

Posted on Friday, June 15th, 2018 in Free PCBs by DP | No Comments

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:

(more…)

Emulating a hardware ROM in real time with an STM32F4

Posted on Thursday, June 14th, 2018 in hacks by DP | 1 Comment

Screen-Shot-2018

 

ROM emulation using an STM32F4:

I remember reading dhole’s  Emulating a GameBoy Cartridge with an STM32F4 some time ago thinking that it had a lot of applications with respect to old computers. In that article  a STM32F4 microcontroller  ‘pretends to be a ROM chip for a gameboy’. At the start of a bus cycle, an interrupt is triggered in the STM32F4, it then reads the address bus of the gameboy’s 6502, checks the gameboy’s read/write line(s) and pulls data from its internal Flash and presents it onto the data bus long enough for the gameboy to read it, then tristates the databus. There are no wait states. It does this all within the 1000ns of the 1MHz Gameboy CPU clock. For all intensive purposes the gameboy thinks it has a real rom chip attached.

Full details at Kernelcrash.com .

Bit-bang FTDI USB-to-serial converters to drive SPI devices

Posted on Wednesday, June 13th, 2018 in how-to, techniques by DP | 3 Comments

DSC_0023

Scott W Harden writes , “The FT232 USB-to-serial converter is one of the most commonly-used methods of adding USB functionality to small projects, but recently I found that these chips are capable of sending more than just serial signals. With some creative programming, individual output pins can be big-banged to emulate a clock, data, and chip select line to control SPI devices.
This post shares some of the techniques I use to bit-bang SPI with FTDI devices, and some of perks (and quirks) of using FTDI chips to bit-bang data from a USB port. ”

See the full post on Scott Harden’s blog .

Check out the video after the break (more…)

Free PCB Sunday: Pick your PCB

Posted on Sunday, June 10th, 2018 in Free PCBs by DP | 8 Comments

BP-600x373

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:

(more…)

App note: How to select an ambient light sensor for your end equipment

Posted on Sunday, June 10th, 2018 in app notes by DP | No Comments

an_ti_sbea006

Another application note from Texas Instruments about ambient light sensors and how to effectively use them. Link here (PDF)

Generally, when someone thinks of trying to design a system with an ambient light sensor there are four main concerns or problems that need to be addressed. The most important features of an ambient light sensor are spectral response, power, size, and range of lux measurement.

App note: How to isolate signal and power in isolated CAN systems

Posted on Sunday, June 10th, 2018 in app notes by DP | No Comments

an_ti_slla386

CAN system isolation app note from Texas Instruments, Link here (PDF)

With the increase in the usage of signal isolation in many industrial and automotive applications, the need for isolated power has also increased. The benefits of isolation are lost if the power supplies on either side of the isolation barrier are simply shorted. At the same time, if the isolated power sub-systems are not designed carefully, it affects the overall system performance like temperature rise due to poor power transfer efficiency, data corruption due to emissions, and so on. To simplify the design process of isolated CAN sub-systems, this document provides various options (discrete and integrated) to isolate CAN signals and power.

ESP32 and the CWTD ‘Test gadget’

Posted on Thursday, June 7th, 2018 in DIY, testing by DP | No Comments

esp32 test gadget

DuWayne published a new build:

I have been following a series of podcasts from ‘Chatting with the Designers’  CWTD.ORG that cover building simple Arduino based test equipment.  I decided that this would make a nice way to get into development with the ESP32.  The CWTD ‘Test Gadget’ is basically an Arduino Nano with a 2 line LCD display, and a breadboard area where small modules can be plugged in to make different types of instruments.  My version will use the ESP32 and the TFT display.  I am also replacing their rotary encoder with a joystick for the user interface device.  I am bringing all the pins from the ESP32 module out to two pairs of female headers, that should allow me to plug in two small modules at the same time.

See the full post on DuWayne’s Place blog.

Siglent SDG6000X Series Arbitrary waveform generator review, teardown and experiments

Posted on Wednesday, June 6th, 2018 in Teardowns by DP | No Comments

SDG6000X-300x149

A closer look at the newly released Siglent SDG6000X Series Arbitrary Waveform Generator from The Signal Path:

The full teardown of the unit reveals the internal architecture of the instrument, DAC / FPGA interconnect as well as the output amplifier structure. Although the limitations of the FPGA prevents the instrument to operate at full 2.5GSa/s in arb-mode, the instrument is capable of providing complex modulation up to the full 500MHz signal bandwidth.

More details on The Signal Path blog.

Check out the video after the break. (more…)

Transistor radio series: the AF power amp

Posted on Wednesday, June 6th, 2018 in RF by DP | No Comments

AF Power Amp

Vasily Ivanenko @ QRPHB writes, “I sought a low distortion, single supply, AF power amplifier for my transistor radios. I’ll present my experiments, some musings, test equipment and a reference to some wonderful books & their wise author. Sadly, some amateur radio receiver builders diligently craft their RF stages, but skimp on the PA audio stage. Actually — many commercial radio designers also do this.”

More details at QRP HomeBuilder blog.

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Recent Comments

  • KH: TPS62200 will get him to under 15uA, a bit better than the 20-30uA he mentioned. I would try the same thing. Switch some resistors in...
  • KH: Yeah, it's an end-user thing. Very few people would spend hundreds of hours on this kind of project and sustain it. It's more or less...
  • Max: Not quite a dinosaur if you've seen Big Hero 6 though... wait. You've watched it with your kids, didn't you? That's cheating...! ;) One of...
  • Edward Mallon: A visiting researcher dropped by our humble basement workshop with questions about the physical skill level students would need if they added one of our...
  • KH: And that looks really expensive... Only browsed the vid though, I'm an dinosaur so I had the sound off too. Nice of him to open-source...