Oscilloscope Thinks It’s A Video Monitor

March 30, 2011 by Jeff Katz 13 Comments

There is nothing wrong with your television set. Do not attempt to adjust the picture.

Where would we be if we listened to advice like that? [Eric] writes that with a fairly simple circuit, he’s able to split a composite video signal into its constituent X and Y ramp signals for display on his trusty Tektronix 465m. A LM1881 IC does the bulk of the heavy lifting. After running the signal through a few passive components, the generated ramp signals are ready for consumption by his venerable ‘scope. All that’s needed past that is some additional glue logic to invert the levels so the image shows up properly. The end result is a display that has an almost ethereal quality to it, like an old TV set or something out of the movie Brazil.

Hit the break to catch a video of the circuit in action.

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Adding Digital Storage To An Analog Scope

March 16, 2011 by Mike Szczys 14 Comments

This is a hack in the finest sense of the term. It not only allows you to capture data from an analog oscilloscope for later analysis, but provides you with a great tool if you’re posting on the Internet about your projects. [J8g8j] used an empty cashew container to add a camera mount to the front of his scope. This is possible because the bezel around the display has a groove in it. A bit of careful measuring helped him make an opening that was just right.

You can see that the red cap for the jar holds the camera and gave him a bit of trouble in the original prototype. This version has a tray where camera sits, which replaces the Velcro with didn’t hold the camera level the first time around. He’s also painted the inside of the clear plastic to reduce glare on the oscilloscope readout. Black and white images seem to come out the clearest, but it can be difficult to make out the grid lines. The addition of LEDs to help them stand out is one of the improvements we might see in the future.

TV Oscilloscope

March 7, 2011 by Kevin Dady 25 Comments

Need an oscilloscope? Want to see the music? Don’t have money, but do have a old TV? Then this TV to oscilloscope mod may be right up your alley. Now don’t go running off just yet, when you’re working inside of a CRT device you are exposed to mains current, high voltage, and high frequency, so extra care needs to be observed .

If you have your rubber welding gloves, and have discharged all your fat capacitors (including the CRT) its pretty much the same magic trick as couple we have previously featured. Patch an amplified input signal into the vertical deflection coil and let her go, but this instructable features much more detailed instruction, and photos so you have a much better chance of replicating this (not quite lab grade) potentially useful device.

Join us after the break for a short video.

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Giant Oscilloscope Music Display

February 28, 2011 by Mike Nathan 9 Comments

oscilloscope_wall

[Andrew] sent us a video of his home made oscilloscope wall, which he uses to visualize different audio tracks he has created. The wall is made up of nine old broadcast monitors he wired together in his studio. At first it appears that the monitors are split into two sets of four, with the center monitor running separately, but upon further inspection it looks as if he can control the display of each monitor independently.

We’re pretty sure he is not using an actual oscilloscope to generate the visuals, but rather visualization software that can approximate the output of an O-scope set in X-Y display mode. Though the screens run independently, it would be great to see all nine screens working in concert to display one large visualization. [Andrew] mentions that an high-def version is in the works, so perhaps we’ll see more features added in that iteration.

Stick around to watch a video of his oscilloscope wall in motion.

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Reverse Engineering Shopping Cart Security

February 28, 2011 by Mike Szczys 30 Comments

All this talk about 555 timers is causing projects to pop out of the woodwork like this one that reverse engineers a shopping cart security mechanism. The wheel seen above listens for a particular magnetic signal and when encountered it locks down the yellow cowl, preventing the wheel from touching the ground and making the cart very hard to move.

[Nolan Blender] acquired one of these wheels for testing purposes and he’s posted some details about the hardware inside. But the first thing he did was to put together some test equipment to help find out details about the signal that trips the mechanism. He connected a coil to an audio amplifier and walked around the market looking for strong signals. Once he found a few strong bursts with that equipment he grabbed an oscilloscope, hooked it to the coil, and made some measurements. He found an 8 kHz signal at a 50% duty cycle at 30 ms intervals (it would be hard to make a better case for why you need an oscilloscope).

With the specs in hand, [Nolan] grabbed two 555 timers, an audio amplifier, and a 200 turn antenna around a ferrite core to build his own locking mechanism. If you’re ever stopped short in the middle of the market, just look for the hacker at the end of the aisle holding the homemade electronics.

[Photo source]

[Thanks Colin]

Xprotolab: Oscilloscope And Xmega Development Board

February 17, 2011 by Mike Szczys 27 Comments

Here’s a nice hands-on overview of the Xprotolab, a development board based around the AVR ATxmega32A4 microcontroller. The tiny DIP package includes an OLED display, four tactile switches, and it can be powered via a micro USB connector. The device ships ready to use as a two-channel Oscilloscope, but check out how small it is in the video after the break to decide if this will actually be useful for you. It’s not that it doesn’t have a lot of features, in fact it’s packed with them, but that screen is quite small for meaningful work. Still, at $35 it’s an inexpensive way to get your hands on the hardware and acquaint yourself with this line of microprocessors. Not that in order to flash new firmware you will need a PDI capable programmer. Continue reading “Xprotolab: Oscilloscope And Xmega Development Board” →

Double The Hertz, Double The Pleasure

November 24, 2010 by Joseph Thibodeau 41 Comments

[tinhead] has opened up a Tekway DST1102B oscilloscope and doubled its bandwidth to 200MHz, sharing his work in the eevblog forum. This is great news to anyone who is looking for a faster sampling rate but can’t afford the high-end models. Mind you, for a lot of us even these Hanteks and Tekways are hard to afford but there are more appropriate options for the ramen-dependent hacker.

In the hacking guide [tinhead] includes comprehensive information on the different scopes he originally considered (a Rigol, Atten and UniTrend) before settling on the Tekway, as well as links to regional distributors for the hackable scope. Good quality benchtop units are invaluable for development and troubleshooting, and it pays off to understand their inner workings. It’s heartwarming to know that even the tools of hacking can be hacked.