by ajoyraman @ instructables.com:
USB connected TI TMS320F28027 based ZRLC Tweezers with
Most Digital multi-meters measure Resistance and Capacitance and LC-meters can measure Inductance and Capacitance. Presented here is a ZRLC meter which can measure Resistance, Capacitance, Inductance and Complex Impedance.
The hardware is built around a TMS320F28027 micro-controller an 8-port-analog-switch ADG714 from analog-devices and a Microchip rail-to-rail dual operational-amplifier MCP6022.
USB Tweezers for ZRLC measurements - [Link]
ajoyraman posted a tutorial on how to make a DIY USB-matchbox oscilloscope, an instructable here:
In order to economize on the cost of an enclosure while still providing an aesthetic unit the Aj_Scope2 is enclosed in a large size cardboard matchbox enclosure.
The USB connection to the PC is on one end while the Audio-Jack for the signals to be monitored is on the other.
A ‘Busy’ LED is provided on one corner at the top and a ‘Reset’ switch is provided diagonally opposite.
The ‘Reset’ switch provides a restart of the micro-controller is the worst-case of hang-up. This typically occurs when the operator selects a trigger threshold which is out of limits with respect to the waveform being observed. If the Aj_Scope2 is operated correctly this switch is seldom used.
DIY USB-Oscilloscope in a matchbox - [Link]
by Glen Chenier @ edn.com:
What I asked for was a general purpose 5GSa/s 1GHz four-channel bench scope. What I got was a 1GSa/s 100MHz two-channel. Still, it is somewhat usable, and less expensive than a fancy temperature-controlled soldering station. But it has bugs – many bugs.
I have been negotiating with the manufacturer to get a firmware update to fix these bugs. After five months, no results. This scope has been designed to accept firmware updates. Good planning. It needs them – desperately. (“Ship now and fix the bugs later. We have a schedule to keep!”)
Before listing all the functional problems, let me elaborate on what I actually like about this scope. The advertised bandwidth is 100MHz, but when feeding in a 300ps edge (ECL directly into the scope with a BNC-T 50 ohm terminator), the measured scope risetime indicates the bandwidth is more like 140MHz. Hurrah for the analog designers!
The scope…from Hell! - [Link]
The LTC2946 is a high or low side charge, power and energy monitor for DC supply rails in the 0V to 100V range. An integrated ±0.4% accurate, 12-bit ADC and external precision time base (crystal or clock) enables measurement accuracy better than ±0.6% for current and charge, and ±1% for power and energy. A ±5% accurate internal time base substitutes in the absence of an external one. All digital readings, including minimums and maximums of voltage, current and power, are stored in registers accessible by an I²C/SMBus interface. The part’s wide operating range makes it ideal for monitoring board energy consumption in blade servers, telecom, solar and industrial equipment, and advanced mezzanine cards (AMC).
LTC2946 – Wide Range I2C Power, Charge and Energy Monitor - [Link]
by Arthur Pini @ edn.com:
Modern mid-range oscilloscopes have more features than most engineers ever use. This article summarizes ten oscilloscope applications that may surprise you. In any event, you may find them useful.
Use the oscilloscope’s fast edge feature and math operations to make frequency response measurements
Frequency response measurements require a source signal that has a flat spectrum. By utilizing the fast edge test signal of the oscilloscope as a step source it is possible to derive the impulse response of the device under test using the scopes derivative function. This can then be applied to the FFT (Fast Fourier Transform) function to obtain the frequency response. Figure 1 shows the steps in the process for both the frequency response of the input signal and that of a 37 MHz low pass filter.
10 tricks that extend oscilloscope usefulness - [Link]
Freq Show: Raspberry Pi RTL-SDR Scanner is a new guide in the adafruit learning system:
Have you ever wondered what’s in the radio waves zipping invisibly around you every day? Software-defined radio (SDR) is a great tool to explore radio signals using a computer and inexpensive radio tuner. With SDR you can examime many radio signals such as FM radio,television, emergency & weather radio, citizen band (CB), and much more.
Although dedicated SDR hardware like the HackRF allow you to tune an immense range of the radio spectrum, you can easily get started with SDR using a Raspberry Pi and inexpensive RTL-SDR tuner. Inspired by the HackRF PortaPack, this project will show you how to build a small portable SDR scanner using a Raspberry Pi, PiTFT, and RTL-SDR radio dongle. With the Raspberry Pi Freq Show RTL-SDR scanner you can visualize the invisible world of radio!
Freq Show: Raspberry Pi RTL-SDR Scanner - [Link]
by EEVblog @ yoututbe:
What’s inside the new FLIR TG165 Visual IR Thermometer / Thermal Camera using the new Lepton sensor?
How does it compare to the FLIR ONE & FLIR E4?
Does it have a calibration shutter?
Does it have any extra capability built in ready to be hacked?
How easy is it to open? (SPOILER – it’s a BASTARD!)
EEVblog #669 – FLIR TG165 Thermal Imager Teardown - [Link]
by TheSignalPathBlog @ youtube.com:
In this episode Shahriar takes a detailed look at an Agilent (Keysight) E4407B ESA-E Spectrum Analyzer. The instruments reports an “Unlock LO” error message which prevents internal alignments from being performed. Before the repair process can begin, the firmware of the instrument must be updated. The firmware upgrade requires the installation of additional flash memory ICs which is presented in the video. The main processor board with its various components are also described in the video.
The complete block diagram of the spectrum analyzer is presented with a detailed look at the principle of operation of the instrument. All the main functional blocks such as the YIG Oscillator, Phase Detector, LO Path, LO Amplifier, Charge Pump, Pre-tune segments, digital circuits, IF and LO paths are analyzed both in schematic and on the PCB. Several potential faults are investigated and measured.
Teardown, Analysis and Repair of an Agilent E4407B ESA-E Spectrum Analyzer - [Link]
by Dave Rishavy @ edn.com:
Noise on a signal creates a triggering challenge for test equipment, especially oscilloscopes. Because the instrument itself also contributes noise, small signals in the millivolt range need proper instrument settings prevent noise from overwhelming the signal of interest. Even with larger-amplitude signals, noise can create a condition where a stable trigger is difficult to achieve.
Oscilloscope have built-in features to help deal with the noise. These features can sometimes be buried in menus, or not well known by infrequent oscilloscope users.
View noisy signals with a stable oscilloscope trigger - [Link]