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Calibration gear. Build a Basic Audio Distortion Analyzer. Over the years with different companies I have worked for, I always had access to high-end audio THD (Total Harmonic Distortion) analyzers.

Build a Basic Audio Distortion Analyzer

I found these very useful for design work, debugging, and repair of audio equipment. My present company has no need for them and consequently they aren’t included in their armory of test equipment. Oftentimes, I have need for one but could never afford to own one — not even a used one. I thought this would be a worthwhile project, so the following article will describe my experience and all the details on how to construct one if you so desire. I had never delved into the internal details of these instruments but did know the basic architecture of how they operated. So, I drew up a design that would have acceptable performance and laid down the target specs I wanted to achieve. As I mentioned, some commercial units have an incredible level of performance, but do we really need that level?

Consider this. FIGURE 1. Can You Trust Your Voltmeter? Sometimes I wonder which of my portable digital voltmeters I can trust — the B&K, Fluke, or Amprobe.

Can You Trust Your Voltmeter?

Usually, they’re pretty close but it bugs me not knowing whether they are right on the nose. Of course, I’m just being picky because I seldom need more than three or four digits of accuracy, but it sure would be nice to know the answer. Fortunately these days, there are a number of very accurate voltage reference circuits that you can build or purchase for a few dollars. A ready-to-use unit made by Agilent is shown in Figure 1. FIGURE 1. It puts out 2.500, 5.000, 7.500, and 10.00 volts and costs less than $20 on eBay. Or … you can build your own reference out of parts in your junk box. #89: Video Tour of my Lab and Workbench - Oscilloscopes and meters and power supplies, oh my!

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Curve Tracer (advanced) Arbitrary Waveform Function Generator, A Comprehensive Tutorial. Mueller Electric Company. LCR. Vintage Gear - Analog Design. True Audio: Audio Spectrum Analyzer and Loudspeaker Design Software. 8 Lens 10x 15x 20x 25x Headband 2LED Watch Repair Magnifier Magnifying Loupe 989 - US$10.48. Tek scope. FPGA Based Logic Analyzer. The outcome of this project is a logic analysator for home use.

FPGA Based Logic Analyzer

The project includes the actual analyzer in VHDL (for Spartan 3 FPGA) and a PC Software for the end user. The design employs a FPGA board that can be obtained easily. Features 16 channels at 200MHz sampling rate 32 channels up to 100MHz sampling rate state analysis up to 50MHz using external clock 256KSamples memory noise filter complex serial and parallel trigger with four stages externally available sampling clock to drive add-ons (like ADCs) connects via EIA232/RS232 (works with usb to serial adapters) Java based viewing software (see PC Client for details) I2C & SPI protocol analysis Hardware The device uses a Xilinx Spartan 3 Starter Kit (DO-SPAR3-DK) evaluation board manufactured by Digilent. To construct a comparable board from scratch would be a tough task for a home project. FPGA VHDL Model To learn how to communicate with the analyzer read: Communications Protocol Client Logic Analyzer Client License Downloads Archive.

Open-workbench-logic-sniffer-p-612. Basil Watson | 2012-09-02 Intermittent Logic Sniffer I purchased unit ver 1.01 some time back . It worked for about a year. It now works very intermittently. I have tried loading all version of firmware but no success. Hi,you can sent e-mail to designer of this project).And thank you for your understanding. Answered by Jacket Chueng | 2012-09-05 Was this useful? 74LVCH16245, for 1.8V support Hi, why not use a 74LVCH16245 input buffer instead of the 74LCX16245?

Hi Eric , sorry that we don't quite familiar with this products because it was designed by dangerousprototype.Please ask on the official website Thanks for your understanding. Deray Wu | 2012-08-20 Was this useful? Teelock Shailesh | 2012-05-08 comunication of spi ,12 n usart i would like to know if the workbench sniffer does Protocols 1-Wire, I2C, SPI, JTAG, asynchronous serial (UART), MIDI, PC keyboard, HD44780 LCDs, and generic 2- and 3-wire libraries as in BUS Pirate Version 4.

Philips scope

The GR 1650 Portable Bridge. Overview The 1650-A was introduced in 1959.

The GR 1650 Portable Bridge

It's a solid 1% performer and like most GR products can do slightly better than that if carefully set up. I always have one around in case I need to measure components on a service visit, or sometimes just to teach someone how to use a traditional mechanical bridge. Though it doesn't have the absolute accuracy of the 1608-A or a Digibridge, it's plenty accurate for most projects.

It can also match parts to a much higher level of accuracy by noting meter deflection, something useful when constructing stepped attenuators for audio projects or other work where tightly matched components are needed.


Distortion measurment. Transistor match. Precision capacitance meter. Use a transistor and an ammeter to measure inductance. JBTech pure technology inside.