Teardown, Analysis and Repair of an Agilent E4407B 26.5GHz ESA-E Spectrum Analyzer


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.

Dino-Lite USB Digital Microscopes Review and Experiments


In this episode Shahriar takes a close look at some of Dino-Lite’s USB Digital Microscopes and accessories. Two of the microscope stand offerings from Dino-Lite are demoed (model MS36B and RK-10) with a close look at their features and usability. All USB stands offer precision Aluminum bodies and flexible ranges of motion for a variety of viewing angles and distances.

Three USB Digital Microscopes from Dino-Lite are also demoed: models AM4113ZTL Dino-Lite Premier, AM4515ZTL Dino-Lite Edge and AM4815ZTL Dino-Lite Edge. These microscopes offers features such as large magnification combined with long working distances, adjustable polarizer, adaptable cap design, MicroTouch shutter button, extended depth of field (EDOF), extended dynamic range (EDR) and automatic magnification reading (AMR) which are all compatible with the provide DinoCapture 2.0 interface software.

Using Dino-Lite’s microscopes, a variety of electronics components are presented: An Analog Devices PCB containing 0102 footprint components, A PIC UV erasable Silicon die, a 325GHz horn antenna, a composite wafer probe with 150um pitch from GGB industries. Finally, the complete breakdown of a QuinStar mm-wave PA module is shown with microwave filters, pre-amplifiers, and a Wilkinson-based GaAs PA as a final stage.

Tutorial on the Theory, Design and Characterization of Delta-Sigma Analog to Digital Converters


In this episode Shahriar explores the world of Delta-Sigma modulators with emphasis on a Delta-Sigma Analog to Digital Converter (ADC). The basic concepts of analog to digital conversion is presented, particularly with respect to quantization noise spectral shape and power density. Next, oversampling ADCs are presented to demonstrate the possibility of increasing SQNR (ENOB) through manipulation of quantization noise spectrum.

Due to the practical limitations of high oversampling ratios, delta-sigma modulations is explored. The principle operation behind delta-sigma ADCs is presented with detailed explanation on noise shaping, filtering and decimation. The signal and noise transfer functions for a 1st order and 2nd order delta-sigma ADC are derived. Finally, as a practical example, a 2nd order delta-sigma ADC based on a 1-bit quantizer is presented. The ADC uses two Miller integrator op-amps, one comparator and a D-Type flip-flop. The complete measurement of this delta-sigma ADC is presented. The impact of over sampling ration, op-amp linearity and input signal bandwidth is presented. The slides for this video can be downloaded here.

Tutorial on Programming the NeoPixel (WS2812) RGB LEDs & Equipment Giveaway!


In this episode Shahriar takes a close look at programming the popular NeoPixel RGB LEDs using a PIC microcontroller and C-language. A close-up of the NeoPixel (WS2812) LED is shown with attention to identifying various semiconductor elements inside the package. The principle operation of the LED is the described along with a detailed explanation of the pins and the one-wire communication protocol.

A simple evaluation board for the PIC18F4550 is used to drive a circular array of 60 NeoPixel LEDs from Adafruit. After presenting the difficulties of providing an accurate pulse-shape using the C-language, the measured waveform is shown on a Tektronix MDO4000B. Finally, the code for a circular color rotating pattern is presented and demoed. The code for the experiment can be downloaded here.

There is also equipment giveaway! A TPI Scope Plus 440 and a Tektronix TDS2232 are being given away at no charge! Please leave a comment on the video or on the website. You must be a resident of the USA to receive the giveaway. A winner will be chosen at a later date and notified via email.

Agilent 53131A Universal Counter Upgrade OPT-030 Analysis and Experiments


In this episode, Shahriar upgrades an Agilent 53131A Universal Counter with the OPT-030 which extends its frequency range from 225MHz to 3GHz. The upgrade kit is a replica PCB intended to emulate the behavior of the original Agilent branded option.

The PCB is examined carefully with attention to microwave layout techniques along the signal path. The datasheet of all the parts are reviewed and the reverse-engineered block diagram of the PCB is presented. The expected behavior of the PCB is then measured in both small-signal and large-signal operation using an active 3GHz probe. The PCB is then installed inside the unit and the functionality of the instrument is verified within its specifications. All the documents presented in the video can be found here.