A while back, I posted a review of the Analog Discovery 2, which is one of those USB “do everything” instruments. You might recall I generally liked it, although I wasn’t crazy about the price and the fact that the BNC connectors were an extra item. However, in that same post, I mentioned I’d look at the device’s capabilities as a network analyzer (NA) sometime in the future. The future, as they say, is now.
What’s an NA?
In its simplest form, there’s not much to an NA. You sweep a frequency generator across some range of frequencies. You feed that into some component or network of components and then you measure the power you get out compared to the power you put in. Fancy instruments can do some other measurements, but that’s really the heart of it.
The output is usually in two parts. You see a scope-like graph that has the frequency as the X-axis and some sort of magnitude as the Y-axis. Often the magnitude will be the ratio of the output power to the input power as a decibel. In addition, another scope-like output will show the phase shift through the network (Y-axis) vs frequency (X-axis). The Discovery 2 has these outputs and you can add custom displays, too.
Why do you care? An NA can help you understand tuned circuits, antennas, or anything else that has a frequency response, even an active filter or the feedback network of an oscillator. Could you do the same measurements manually? Of course you could. But taking hundreds of measurements per octave would be tedious and error-prone.
Continue reading “Analog Discovery 2 As A Vector Network Analyzer”
I recently opened the mailbox to find a little device about the size of White Castle burger. It was an “Analog Discovery 2” from Digilent. It is hard to categorize exactly what it is. On the face of it, it is a USB scope and logic analyzer. But it is also a waveform generator, a DC power supply, a pattern generator, and a network analyzer.
I’ve looked at devices like this before. Some are better than others, but usually all the pieces don’t work well at the same time. That is, you can use the scope or you can use the signal generator. The ones based on microcontrollers often get worse as you add channels even. The Analog Discovery 2 is built around an FPGA which, if done right, should get around many of the problems associated with other small instrumentation devices.
I’d read good things about the Discovery 2, so I was anxious to put it through its paces. I will say it is an impressive piece of gear. There are a few things that I was less happy with, though, and I’ll try to give you a fair read on what I found both good and bad.
Continue reading “Review: Digilent Analog Discovery 2”
It’s been a little while since we talked about HDCP around here, but recent developments in the area of digital content protection are proving very interesting.
You might remember that the Master Key for HDCP encryption was leaked last year, just a short while after Intel said that the protection had been cracked. While Intel admitted that HDCP had been broken, they shrugged off any suggestions that the information could be used to intercept HDCP data streams since they claimed a purpose-built processor would be required to do so. Citing that the process of creating such a component would be extremely cost-prohibitive, Intel hoped to quash interest in the subject, but things didn’t work out quite how they planned.
It seems that researchers in Germany have devised a way to build such a processor on an extremely reasonable budget. To achieve HDCP decryption on the fly, the researchers used a standard off the shelf Digilent Atlys Spartan-6 FPGA development board, which comes complete with HDMI input/output ports for easy access to the video stream in question. While not as cheap as this HDCP workaround we covered a few years ago, their solution should prove to be far more flexible than hard wiring an HDMI cable to your television’s mainboard.
The team claims that while their man-in-the-middle attack is effective and undetectable, it will be of little practical use to pirates. While we are aware that HDMI data streams generate a ton of data, this sort of talking in absolutes makes us laugh, as it often seems to backfire in the long run.
[via Tom’s Hardware]
[Will] wrote in to share a useful add-on he designed for the ChipKIT UNO 32, a 12-port temperature sensor board.
Constructed for one of his customers, the shield accepts any 2-wire 10k thermistor sensors, outputting the readings to a small LCD screen. The screen is supported by some code put together by his associate [crenn], but you are not limited to solely displaying the temperatures there. Since this module piggybacks on top of the ChipKIT the same fashion as any standard shield, you clearly have the ability to use and manipulate the data at will. With 12 ports on board this would work well for a house-wide temperature monitoring system, or perhaps in a complex brewing setup.
Both the temperature shield and LCD boards have been released under the Open Source Hardware License, so you can easily build your own if you have the means, though [Will] has a few extras he’s willing to sell if you need one quickly.
Following Maker Faire, we’ve had a few days to poke around with Digilent’s 32-bit Arduino-compatible chipKIT boards and compiler. We have some initial performance figures to report, along with impressions of the hardware and software.
Continue reading “ChipKIT Uno32: First Impressions And Benchmarks”
If you’ve been hungry for more power for your microcontroller projects, but reluctant to dump your investment in Arduino shields or the libraries and community knowledge that go with them all, Digilent has you covered. Their new chipKIT boards are built around the Microchip PIC32 MCU…a powerful 32-bit chip that until recently was left out of the cross-platform scene. A majority of code and quite a number of Arduino shields will work “out of the box” with the chipKIT, and the familiar development tools are available for all three major operating systems: Windows, Mac and Linux.
We first mentioned these a couple weeks ago, but the software was unavailable at the time. Seeing the development tools in action was quite unexpected…
Continue reading “BAMF2011: ChipKIT Is Arduino To The Power Of 32”