This forum post over at the EEVBlog Forum gives us a great look at the inside of an old Tektronix 465 Oscilloscope and walks through the repair and refurbishment of the scope. The refurbishment isn’t just taking a cotton swab and rubbing out some dirt, it is rather invasive including a complete system dismantle and cleaning. Nice thing about this method is we get to see all of the internal workings of the device! Thanks to ModemHead for taking the time for documenting this.

Have a look at this fun project called the Shy Light. The light doesn’t like to be seen in public and uses a basket to hide in. X10 and two microcontrollers are being used to get the job done.

“Why TWO Microcontrollers? The Dual-Microcontroller Circuit: Master (right) Slave (left) The Master Control microcontroller handles the foot-switch input, orchestrates the timing of the opening/closing of the basket (using commands to the Slave Control unit) and the lamp dimming. Initially, I had no idea that the project would require two; there are enough analog and digital pins on one microcontroller to do it all, but—and I’m not absolutely certain about this because I didn’t keep detailed notes about this—I think that I was forced into a dual processor arrangement because of the complexity of the program timing. As I designed the circuit, I came to the realization that the timing required by the various elements was going to be difficult for me to accomplish as an amateur C-coder if I tried to stuff it all into one controller. So I don’t want to say that “it can’t be done with one chip”. I just decided that it was simpler for me to compartmentalize the various tasks with hardware. So I added another ATMEGA168, at an added cost of about $5.00.”

Bruce sent in a link to this cool picture of a very old display in this 1901 picture (top of the tallest building in the picture). It looks to be a primitive 16 segment display. The building is The Great Coal Mine, Coney Island. I wonder what the display was used for? Below you can see the modern version of this display.

“The Great Coal Mine was a 1,500-foot-long dark ride that enabled visitors to travel on coal cars through several levels of a dimly lit simulated mine. It opened in 1901 on the north side of Surf Avenue at West Tenth Street, was not very popular, and was soon replaced by L.A. Thompson’s Oriental Scenic Railway.”

Who would have thought that in 2012 we would have a need for Nixie tube testers since this was a technology that was only developed and used because things like LEDs didn’t exist. Since the technology is so cool it has remained as a technology that is used in some DIY kits and projects.

Thanks for sharing this with us Vassilis.

“A simple device for testing and/or healing Nixie tubes of IN-18 type. An 11-pole switch is connected in series with a 50 KΩ pot (+ 470 Ω resistor for safety), powering from an 180V DC source. Normal operation at 2 mA is shown. “

If you like steampunk you will want to watch the video below where fellow Canadian Robert Shuttleworth from shuttlewerks / ephemera shows us how he builds a webcam from an old electric heater.

“Steam punk webcam built from a 1930′s electric heater. Not technically difficult and should cost under $50. Resulting image is old time Alice Through the Looking Glass”

If you think about the technology in the 70s and wonder what a home made calculator would look like this is exactly what I have in mind. A wooden box is used to house multiple small circuit boards and reams of colored wires connect everything together. I remember hearing about the Woz designing many of his creations on paper rather than with actual electronics since the parts were so expensive. In this case the cost of purchasing a similar calculator made building one from scratch a viable option. This is almost unthinkable these days where you can get a calculator for less than a dollar and it has a built in battery and solar power as a backup!

Via Hack a Day

“Back in the good old days of the early 1970s, small desktop calculators were made by several companies. However, they cost quite a lot of money. The average engineer didn’t have that much cash lying around, but still wanted to relieve himself of the burdens of manual mathematical computations.”

Tired of watching your flat panel LCD and miss the days when you were trouble shooting your circuits with a CRT scope? You can have the best of both worlds with this circuit. CameramanLink designed the circuit below to make it happen. If you have a few hours to kill have a look at the ton of projects that CameramanLink has done!

“Homemade television video monitor built from scratch. It uses a 5″ 5UP1 CRT to display a video image in black and green. This is the fourth of five video display projects I’ve built. After building the 2AP1 T-Vision, I decided to build another similar circuit but with further improved features. This circuit uses 2 multivibrator oscillators with improved linearity to produce the sawtooth waves for the horizontal and vertical scanning. It uses many of the same improvements made to the previous 2AP1 T-Vision: 1) It uses a wide band video amplifier to increase frequency response, allowing for better horizontal resolution, 2) It uses vertical retrace blanking applied to the cathode of the CRT to remove the flyback lines, 3) It uses balanced deflection amplifiers for even focus across the screen.”