Free PCB coupon via Facebook to 2 random commenters

in Free PCBs by DP | 2 comments


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:

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Week in (p)review April 18, 2014

in week in review by DP | 0 comments


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

Programmable VFD display & ticker

in DIY, hacks by DP | 1 comment


Coyt Barringer has been working on a programmable VFD display and ticker project:

The goal was to make a small programmable display so I can quickly check the current Bitcoin or Dogecoin price, see the time, weather, etc as I walk into my room. The display also had to look cool – I tried to make it steampunkish / hipster if you will.
The whole thing is really just a large VFD (Vacuum Fluorescent Display) and a Raspberry Pi, both of which I mounted to a bent metal plate as a stand. There is also a PIR motion sensor which I have setup to put the display to sleep after a set amount of time with no motion in the room. There are green LEDs between the metal plate and the back of the VFD to create a green glow around the edge. The Raspberry Pi is running it’s default debian distro (Raspbian?) and auto connects to wifi on boot, and a Python script controls the VFD through the Raspberry Pi’s serial port.

Posted in DIY, hacks | Tagged , | 1 Comment

RC servo and PID – ‘Autotune’

in DIY, hacks by DP | 0 comments


Stanley Lio‎ is working on a RC Servo and PID autotune project:

The robotic arm built for the magnetic field measurement project leaves several things to be desired.

  • After a new servo is installed, finding the mapping between PWM duration and DH angles is done manually with pen and protractor. I want to automated this.
  • The arm trembles and oscillates at certain poses. I want to be able to tune the PID parameters of the RC servos, and experiment with different control algorithms.

I can use the IMU mounted on the arm to automate these tasks, or even use computer vision. Would be interesting to have the computer auto-tune the PID parameters.
I also want to go one step further and combine computer vision with the arm.
Move the arm with real-time input devices such as mouse, keyboard, gamepad, camera etc.

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JTAG flashing BCM6348 devices with a Bus Pirate and OpenOCD

in Bus Pirate, JTAG by DP | 1 comment


Lee of Sodnpoo writes:

Having never used JTAG before I thought I’d see what I could do with my new Bus Pirate and one of the old ADSL routers I have lying around – ideally reading/writing to the flash. The v1 BT Home Hub is a Broadcom BCM6348-based device with 32MB RAM, that I’d previously added headers for the serial uart and replaced the bootloader with RedBoot and the OS with openwrt. You can see a small breakout with a TTL level converter and an FTDI uart<->USB on the right, and the Bus Pirate on the left in the picture above.

Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.

Posted in Bus Pirate, JTAG | Tagged , , | 1 Comment

DIY laser cutter project

in DIY by DP | 0 comments


Hans Peter of has been working on a Laser cutter project and wrote a detailed explanation on his blog describing the build:

Having seen the crazy-fast development of the printers during the time I’ve had mine, I can clearly see that my printer is not the fastest or the most precise in the league anymore. Most of the newer printers use some kind of lasercut frame or piece somewhere. While I can get to a laser cutter, it takes a lot of time and I’m not guaranteed that it’s available when I need it. so therefore – I want my own. Commercial cutters cost around 45kDKR and up, so that’s a no. Instead, I will be building one on my own.

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1.3”OLED with SSD1306 controlled by Bus Pirate

in Bus Pirate, project logs by DP | 0 comments


Markus Gritsch writes:

I wrote a quick Python script to communicate with an SSD1306 driven OLED connected to a PC with a Bus Pirate. The script uses the Bus Pirates raw SPI mode and manages to update the little screen slightly faster than 10 times per second.

Via the project log forum.

Check out the video after the break.

Get your own handy Bus Pirate for $30, including world-wide shipping. Also available from our friendly distributors.

Continue reading →

Simple electric imp temperature logger

in 3D Model, hacks by DP | 0 comments

2014-01-09 10.20.27

Marcus Olsson of Slickstreamer made this simple electric imp temperature logger with 3D printed case:

I build this temperature logger for my father as a christmas present so he can use his phone to view the temperature at home. The device is build from a electric imp, TMP102 temperature sensor, battery and a charger. It loggs the data to thingspeak.

Hacking a 3D printer into a tattoo machine

in 3D Model by DP | 1 comment


Here’s a cool instructable for a 3D printer tattoo machine:

In october 2013, a famous design school in Paris, ENSCI les Ateliers, hosted a workshop organised by the French Ministry of culture. The idea was to use images, videos and sound fallen in the national pubic domain and use them in a sort of “Mashup”. The event was called Public Domain Remix.

The students had one day (8 hours) to pick their digital material and transform it, hack it or remix it.
Le FabShop, was invited as a digital manufacturing expert to help the students realise their project.
After a short brainstorm, all the teams came up with similar ideas, except one, who really went out of the box with their concept. They had this silly idea of making a machine that could automatically create tattoos taken from a bank of images.

Check out the video after the break.

Via Open Electronics.

Continue reading →

Posted in 3D Model | Tagged , , | 1 Comment

Hacker Camp Shenzhen Day 1: Hot pot dinner

in Hacker Camp Shenzhen, Shenzhen by DP | 0 comments

By ian


Hacker Camp Shenzhen isn’t just about cool markets and amazing soldering techniques, we made food a centerpiece too! Day 1 dinner: Hot pot. Here is the hot pot crew in action! 30 hackers joined us at our favorite hot pot place.

This hot pot restaurant is probably the most popular one in the neighborhood. Five people sit around a charcoal-fired pot filled with boiling broth. Plates of meat and vegetables are delivered all night – just toss in your favorites for a quick boil and eat. Optionally, blend your own dipping sauce at the sauce bar.


Lots of lamb, lots of Tsing Tao, lots of laughter.


The street is still pretty wet, but that didn’t stop us from having fun. People walking by stopped to take photos of all these foreigners.


This restaurant is so popular that it won’t take reservations. So, we came here to eat almost 5 times a week for a month to persuade the owners to rent us the sidewalk for the night.

After lots of begging, one of the owners finally said yes. Frankly speaking, it was only 4 days before the workshop that we sealed the deal.


This is the spicy hot pot team, Gus and Nik are just about to pose, Ian and Akiba are already in full FACE FRAME!

Via Hacker Camp Shenzhen mini-site: Hacker Camp Shenzhen Day 1: Hot pot dinner

The deal with Dirty Cheap Dirty Boards PCBs

in PCB Review, PCBs, site by DP | 17 comments


This sad FACE FRAME! documents the moment Ian found out Dirty PCBs hit Hacker News, Hack a Day, etc. Here’s the story behind our joke PCB site…

A few months ago there were some comments in the forum about various PCB services making ‘crap’ $0.90 boards. Later we posted a picture of our own $0.20 PCB on the blog and the first comment was ‘silkscreen sucks’.  It became an inside joke around here because a few years ago we were all more than happy to pay Olimex $100 for a tiny PCB with no silk…but now people complain about minor things like a smudged silkscreen on twenty cent PCB.

In the forum we joked about about starting a PCB site intended to be crappy: “Dirty Cheap Dirty Boards”. One of our team members, who shall remain nameless, took the joke way too far and made an actual PCB website based on that joke. The site promises cheap and bad PCBs. We used it internally to handle our PCBs, and let a few forum contributors place orders too – easier than doing it all manually.

Here we are, eating hot pot dinner on the street of Shenzhen with the rump end of the hacker camp crew enjoying a Tsing Tao. Phones buzz – order notification. Phones buzz more. And again, and again. Then someone from the HAX group delivers the terrifying news – our little inside joke is on Hacker News. Then it pops up on Hack a Day too.

We hit the comments to say it was a joke and flame the trolls who dissed our flippant attitude (you like it dirty and you’re back for more), but the damage was done.

However, Dirty PCBs wasn’t entirely a joke. The platform combines all of our ideas for a ‘no nonsense’ online ordering platform. No stupid logins with yet another password to remember, no login to get order status, obscene amounts of status updates (email, SMS, Twitter), and a single step ordering process with flat  predictable pricing.

The Dirty Platform is used in two new projects we’re launching. The first is Dirty Circuits – a schematic entry, PCB routing, and footprint building service for open hardware that’s open now. It’s been available privately to some select projects for a while and has been a great success.  Soon, we’ll add Dirty Cables, a way to create custom designed cables from quantity 100. That’s not the end of the Dirty world either, we’ve got more new projects launching soon, all with the goal to help make more and better open source hardware.

Hacker Camp Shenzhen Day 1: Huaqiangbei market tour

in Hacker Camp Shenzhen, Shenzhen by DP | 1 comment

By ian


Huaqiangbei is probably the largest electronics component market in the world. It’s why we’re here for Hacker Camp Shenzhen, it’s why most people are visiting. On day one we broke into four groups and toured the market. Everyone was introduced to guides’ favorite distributors, and we bought a few goodies along the way. Check the day one tour below.


IMG_7484-W600After discussions and before the tour we hit the local Cantonese place for WAY too much food. Joe @ Arcbotics and Ian plan the tour route in the lower left.


The tour wound through the used cell phone markets and past the cell phone components market. Along the way we stopped at the ‘Hokkien Brothers’ shop for a few pre-arranged gifts: screw drivers and solvent dispenser bottles. This is where we buy all our tools, and many people on the tour found their way back here later for tools.


A group checks out the Qinsi pick and place machine on ‘fourth floor’ tool building. It’s very similar to the TM220.


You’ll buy a lot in Huaqiangbei, and it probably won’t fit in your luggage. Suzie shipper provides inexpensive air freight to most of the world, and she’s a must-meet stop on the tour.


Our final stop on the tour is the ‘dodgy cell phone market’. Here you find all sorts of oddities. From $10 credit card sized phones with OLED displays, to 3G replicas of giant 1980′s phones, to this surprise on we encountered accidently on the very last stand of the tour.


This little guy is clearly a MiPhoneK with a cute Android Robot logo.


Though a bit of alcohol reveals the Apple logo and something resembling an iPhone color running Android 4.x. For $40 it’s worth it for the show alone, but there’s some surprises inside we’ll reveal in a future tear down.


After the tour everyone headed back to their favorite stands to forage for treasure. We all exchanged part pr0n via WeChat, a message program that’s super popular in Asia.

Via Hacker Camp Shenzhen mini-site: Hacker Camp Shenzhen Day 1: Huaqiangbei market tour

Dirty Circuits PCB routing for open hardware designs

in PCBs, skills by DP | 0 comments


At Dangerous Prototypes we have a team of amazing PCB designers. We crank out a lot of boards publicly and privately, but even we can’t keep these hungry routing addicts busy all the time. Now we’re lending our routing skills to you for your open hardware project through a new site: Dirty Circuits.

If you have an open hardware project and would like help routing the PCB, we’re here to help:

  • Turn a completed schematic in KiCAD or Eagle into a pretty PCB
  • Turn a stack of Arduino shields and a circuit drawings into a schematic and integrated PCB
  • Turn a hand drawing into a great looking KiCAD or Eagle schematic
  • Build that stack of component footprints you don’t want to do yourself


You can take a look at our previous designs at Dangerous Prototypes. The same routers will work on your PCBs. All designs are hand routed, never autorouted.

Here’s some comments from our private beta testers. A quick fix of inconsistencies that caused a major setback:

..I don’t want it to get weird or anything, but I might kiss you next time I see you. Just sayin’. Huge thanks. Gargantuan colossal thanks. For real, I was sweating bullets about how I’d find time to fix my mess up.

A full board routing:

This looks fantastic. It’s as good as I could have done in Altium, but in Eagle, so I can share the damn design files and have them be useful to people. He even caught that I forgot to add test points for the battery charger and soft power. Hot damn. Hot diggety damn.

We only route the PCB. Any design flaws in the circuit are beyond our control, but we make every effort to route perfect PCBs. In cases where we mess up really bad, we’ll probably fix the design and buy you a new set of PCBs.

What we don’t do…

We are able to route digital designs for open hardware projects. There are many things we don’t want to do:

  • Engineering or design. We just route PCBs, you have to prove the circuit
  • RF or complicated analogue design (impedance balancing, etc)
  • More than 2 layers/10x8CM in Eagle because so few can edit the files (2+ is fine in KiCAD)
  • Closed hardware projects

Keep it Dirty

For more please head over to Dirty Circuits to read the FAQ and submit your boards for routing.

Hacker Camp Shenzhen Day 1: Surviving Shenzhen

in Hacker Camp Shenzhen, Shenzhen by DP | 0 comments

By ian


Each morning of Hacker Camp Shenzhen started with a 2 hour discussion of various Shenzhen and electronics stuff. The first day Ian @ Dangerous Prototypes gave an overview of Shenzhen, food options, and essential life skills for getting around. Jin @ FlyLin gave a crash course overview of Chinese that introduced basics like numbers, hand signals, and how to get “this one”.

Day one presentations are available for download here. Videos will be posted shortly. Check below for pictures of the goodie bags and highlights from day 1 discussions.


Everybody gets a goodie bag! These swag sacs were fashioned from antistatic bags and rainbow ribbon cables with 2

DIY 100W LED flashlight

in hacks, LEDs by DP | 2 comments

In this video Julian Ilett demonstrates his DIY 100W LED flashlight:

I discovered that due to a lucky co-incidence of voltage and internal resistance, a 100W LED can be connected directly across the terminals of two 18V Nickel Cadmium power tool batteries. And that means you can build a 100 Watt (7,500 Lumens) flashlight for less than $10 (not including batteries).
Note: Don’t try this with other battery types – you’ll almost certainly fry the LED!

Via Hacked Gadgets. Continue reading →

Posted in hacks, LEDs | Tagged , | 2 Comments

Laserworld CS-500RGY laser projector teardown

in Teardowns by DP | 0 comments


Jaanus did a teardown of a Laserworld CS-500RGY laser projector:

I got my hands on a Laserworld CS-500RGY laser projector. This is the smallest 500 mW one. It is a device that has three laser sources (red, red and green) and mirrors for moving laser pointer. It can be controlled by sound, DMX512 or ILDA interface. So, lets tear it down.

Review: building publicLab’s DIY spectroscopy kit

Rohit writes,

I made a Opensource Spectroscope using the publiclab’s kit. I was surprised to see the kind of accuracy you can get from these easy to make Spectroscopes. I probed around a lot of light sources like LEDs, Sunlight, Tubelights and Bulbs. With LEDs I was able to estimate the forward drop in a RGB Strip for the different colors very accurately. The spectrographs of Sunlight confirmed the presence of IR and UV. The bulb’s spectrograph showed that it emits large amount of IR.The Tubelights ones showed that it is designed to render light very close to sunlight.

Quite Amazing science from a very easy to make scope.

You can read Rohit’s description of the build and review on his Indian Tinker blog and also at Instructables.

#FreePCB via Twitter to 2 random RTs

in Free PCBs by DP | 0 comments


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.

miniLOG – Precision standalone voltage logger

in Arduino, project logs by DP | 1 comment


Jakub Felcenloben over at Electronics Lab has written up documentation on his latest project called miniLOG, a basic data logger:

miniLOG is a precise standalone voltage logger that save the data on a SD card. It has 4 basic analog channels:

  • one has 12bit resolution for voltage measurements,
  • two channels have 10bit resolution for voltage measurements and
  • one channel has 10 bit resolution for current measurements.

Input voltage range is 0-25V and current range is 0-500mA. The data are written on a simple .txt file on SD card and can be further proccessed using spreadsheet software.