Monthly Archives: December 2016

Die photos and analysis of the revolutionary 8008 microprocessor, 45 years old

via Dangerous Prototypes


Ken Shirriff has written an article detailing die photos of the vintage Intel 8008 that reveal the circuitry it used:

Intel’s groundbreaking 8008 microprocessor was first produced 45 years ago.1 This chip, Intel’s first 8-bit microprocessor, is the ancestor of the x86 processor family that you may be using right now. I couldn’t find good die photos of the 8008, so I opened one up and took some detailed photographs. These new die photos are in this article, along with a discussion of the 8008’s internal design.
The photo above shows the tiny silicon die inside the 8008 package. (Click the image for a higher resolution photo.) You can barely see the wires and transistors that make up the chip. The squares around the outside are the 18 pads that are connected to the external pins by tiny bond wires. You can see the text “8008” on the right edge of the chip and “© Intel 1971” on the lower edge. The initials HF appear on the top right for Hal Feeney, who did the chip’s logic design and physical layout. (Other key designers of the 8008 were Ted Hoff, Stan Mazor, and Federico Faggin.)

More details at Ken Shirriff’s blog.

Radioactivity detection using very simple ionization chamber and a single J-FET transistor

via Dangerous Prototypes


Robert Gawron writes:

Today I will show a very simple ionization chamber that can detect radioactivity. I was able to detect with it ionizing radiation from a smoke detector (Am241 isotope). It’s also immune to electromagnetic interference (EMI) due to a good shielding.

This device doesn’t explicitly use any power supply. It’s connected to a multimeter set to measure resistance, in this mode, the multimeter provides a small voltage to its probes (R=I/U, so to measure resistance, it has to put voltage across measured element). This is sufficient here, because basically we just need to polarise electrodes of the ionization chamber and nothing more. My multimeter provides 5.6V in this mode.
My setup is presented below, note that the sensor is this metal box, not the PCB visible on the image.

More details at Robert Gawron’s blog.

Enginursday: Mort and Mary Present…Fun with Sockets, Part Deux – Old Products Never Die

via SparkFun Electronics Blog Posts

You know how I keep making projects and posts about Moose, my dog? Well, this is also about Moose! Even more about my laziness and how unwilling I am to stand out in Colorado winter temperatures to throw his ball around. His exercise is important to me, though, and now that I can’t be dragged across the pavement safely (because of ice) in the early mornings and late evenings, I’ve had to come up with a new way to keep Moose in good health.

In case you didn’t know, Moose is actually a cat in a very nice dog suit.

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I want to give him the whole backyard to chase that red dot. I want to be indoors with a heated blanket and the internet.

Enter PiMooseCade

This system combines Mort’s Python programming skills, my clumsy hardware coaxing and Moose’s love for finding that red dot. This is a remote-controlled laser pointer. PiMooseCade uses the same socket network setup and message encoding/decoding as the project from last week’s Enginursday post, with the exception that this project is running two sockets—one for the controller data and one for the camera data. Using the parts from my crowning underachievement, the PiRetrocade, Mort and I cobbled together this necessary invention over the holiday break. Let’s start with a crude block diagram.

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The PiMooseCade consists of two separate systems communicating over a socket to provide Moose with all the entertainment he/we need. The first system belongs on my desk. It is the PiRetrocade with a Raspberry Pi 3 reconfigured to map button presses to servo action. Up and Down on the joystick control the tilt, while Left and Right control the pan. An arcade button has been reconfigured to change the delay between each change in servo position. Holding down on A decreases the delay, thereby increasing the speed of changing position by 15X—all Mort’s idea. The second system, which is to be mounted on my back porch awning, consists of a Raspberry Pi 3, SparkFun RedBoard, Pi Camera Module, tilt and pan kit with two servos and a laser pointer mounted on top. From my desk I watch Moose chase after the laser with the video footage from the camera sent to my workstation via the socket. I control the position of the laser with my controller. Each button press is encoded by protobuf and sent over another socket. The Raspberry Pi outside receives the messages and forwards them onto the RedBoard. The RedBoard is running the client protobuf (in the code link below) to decode the messages into servo actions. Yes, I’m sure there was an easier way. And one day it will be made that way by us, but today is not that day.

We have here:

Why a RedBoard? Well, the PWM on the Raspberry Pi is terrible! The servos just jittered about, and the response time was dismal. We tried both software and hardware solutions to no avail. The best we could come up with to get something working quickly was to add a RedBoard to the mix.

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Testing the controls over socket using protobuf. That’s where the laser goes, there on top. Pretty darn zippy.

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Testing the outdoor system, controlled from the office.

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From the laser’s point of view

The Complications—Still a Work in Progress

The video footage caused some major delays in the project’s progress. From my workstation we are VNC’d into both Raspberry Pis. I thought I would be able to capture the video data with Raspberry Pi’s “experimental screen capturing” using omxplayer. No luck.

Then we tried streaming the video footage over a socket from Raspberry Pi 2 to Raspberry Pi 1 using OpenCV then VLC. It was laggy to say the least—sometimes it worked, and sometimes it didn’t.

We tried a few other solutions before Mort came up with the idea of streaming the video footage directly to the workstation by sending the video data through the standard output and netcat'ing it to the workstation’s VLC player. It worked!

“Works like a senior design prototype, semester one, week eight, when you need to show your professor something,” says Mort.

We are still working on getting a less kludgy version up and running at our house. Once we have the system working according to the house spec, the updated files and video will be shared.

Finally! A project for cats as complicated as cats!

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Comfort Thermometer display built with 517 individual LEDs

via Dangerous Prototypes

Richard wrote in to tell us about a ‘Comfort Thermometer display built with 517 LEDs’ that he has just finished building:

Comfort Thermometer Display built with 517 individual LEDs and the following microprocessors:
1) PiC24FV16KA301 – controlling outer 36 RGB LEDs
2) PIC16F886 – bargraph and pink LEDs animations
3) ATmega328 – controlling 7-segment display
4) PIC16F57 – rf transmitter and receiver

The bargraph LEDs are current sinked with LM3914 LED display drivers, and current sourced via the PIC16F886 and transistors

Via the contact form.

DIY IKEA wireless Qi charging for the Hexiwear

via Dangerous Prototypes


Erich Styger built a DIY a wireless charging system for the Hexiwear:

The Achilles Heel of the Mikroelektronika Hexiwear is its charging: the charging and USB connector are only designed for a limited number of plug-unplug cycles, and it does not have a wireless charging capability like the Apple iWatch. Until now! I have built a DIY wireless charging system for the Hexiwear🙂

More details at MCU on Eclipse homepage.

Hardware Hump Day: 3 Soft Electronics Tricks

via SparkFun Electronics Blog Posts

Happy Hardware Hump Day! For the inaugural #hardwarehumpday post, we are going to build a momentary switch button, a coin cell battery holder and an on/off switch using only soft materials. These techniques are an excellent way to make the most of your soft electronics materials and to minimize the use of traditional hardware in soft circuitry.

To follow along, you will need to gather the following supplies:

Coin Cell Battery Holder - 20mm (Sewable)

$ 1.25
LilyPad LED Red (5pcs)

$ 3.95
Conductive Fabric - 12"x13" MedTex130

$ 29.95
Conductive Thread Bobbin - 30ft (Stainless Steel)

$ 2.95
Coin Cell Battery - 12mm (CR1225)

$ 1.95
Needle Set

$ 1.95
Snap Assortment - 30 pack (male and female)

$ 2.95

Let’s start with the momentary push button.

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Start by cutting two small swatches of conductive fabric. Place one on the very corner of your felt and sew it down using the conductive thread. Then, with the same piece of thread, stitch down the felt a few inches before connecting to the LilyPad sewable LED cathode and tie it off. Use the running stitch to connect the LilyPad sewable LED anode to the positive lead of the sewable coin cell battery holder. Place the second patch of conductive fabric at least an inch away from the other, and sew it down to the felt. With the same piece of thread, connect the second patch to the negative lead of the sewable coin cell battery holder. Pop a 3V coin cell battery in and watch the LED illuminate when the two patches touch!

No sewable battery holder? No problem! Let’s make our own with the same supplies.

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Start by knotting your conductive thread on one end about 3 to 4 times. Use the other end to thread the needle and then sew down into your felt from the top side and trim the tail. Use the running stitch to connect it to the cathode of a LilyPad sewable LED and tie it off. Cut a patch of conductive fabric that is ever so slightly wider than the coin cell battery. Place the patch directly on top of your knotted conductive thread and sew down three sides, making a small pocket. Using the same piece of thread, connect the conductive fabric patch to the LilyPad sewable LED anode. Slip a 3V coin cell battery into the pocket with the negative side against the felt and enjoy that bright LED light!

Finally, we are going to use metal snaps to create a soft on/off switch.

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Start by sewing down one side of the metal snap onto the felt using conductive thread. With the same piece of thread, connect it to the cathode of the LilyPad sewable LED using the running stitch and tie it off. Connect the LilyPad sewable LED anode to the positive lead of the sewable coin cell battery holder. Place the second side of the metal snap at least an inch away from the other and sew it down to the felt. With the same piece of conductive thread, connect it to the negative lead of the sewable coin cell battery holder. Put a 3V coin cell battery in and…snap! Let there be light!

Start something soft this season! Share your soft tricks and projects with us on twitter and in the comments below.

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