TNP #44 - AT&T 938A LED Optical Loss Set Repair, Teardown & Experiments
8.6K views
December 14, 2023 8:29 PM
In this episode Shahriar takes a look an AT&T optical loss set which is equipped LED sources 875nm & 1300nm. The unit has been storage for over a decade with heavily leaked batteries.
After the cleanup, the unit powers on and is able to measure optical power as well as generate light from the LED source. The accuracy of the photodetector is verified against a calibrated optical meter. The wavelength of the 875nm LED source is also measured using a spectrometer.
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TSP #236 - A 77GHz Automotive Radar Module Measurement, Reverse Engineering & RFIC/Antenna Analysis
105.9K views
November 30, 2023 10:00 PM
In this episode Shahriar takes a detailed look at two different automotive 77GHz radar modules. Each module design is presented along with the overall architecture and functional blocks.
The working module measurements are presented with discussions on how to capture an FMCW waveform at mm-wave frequencies. The teardown of the faulty module reveals the overall synthetic aperture design, antenna placement and design considerations and the digital backend processing. A close look at the Infineon 77GHz RFICs are also presented.
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TSP #235 - Stanford Research SR650 Dual Programmable Filter HP/LP Repair, Teardown & Experiments
14.6K views
November 25, 2023 11:49 AM
In this episode Shahriar repairs an SRS SR650 dual programmable filter. The unit powers on with nearly all the front-panel LEDs illuminated but does not respond to any buttons. Schematic and internal measurements show a lack of activity on any of the main processor pins which is traced to a faulty inverter IC responsible for clock generation. The main SRAM IC is also missing and needs to be replaced.
Additional analysis of the circuits and modifications are also presented. However, the unit develops a new problem due to very high thermal dissipation of the 5V regular and full bridge rectifier. A new rectifier is installed and the faulty 5V regular is also replaced. The QuantAsylum QA403 Audio Analyzer is used to characterized the filter and ensure both the high-pass and low-pass filter sections are functional.
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TNP #43 - Rohde & Schwarz URE2 DC - 25MHz 300V RMS Voltmeter Teardown, Repair & Experiments
14.3K views
November 23, 2023 6:46 PM
In this episode Shahriar takes a look at a fault Rohde & Schwarz URE2 which is a highly sought after RMS voltmeter. The ability of the RE2 to provide accurate RMS measurement up to 25MHz as well as provide DC measurement makes it an excellent instrument for characterizing DC/DC converter output noise characteristics.
The faulty instrument can measure AC, however no DC measurement can be made. The unit also occasionally generates an error code 0080 which points to a fault in the main analog board. Teardown of the instrument reveals a pair of front-end relays responsible for mode switching which are the likely cause of the DC measurement problem. The relays are replaced and the instrument returns to full operation. The performance and functionality of the unit is verified through several experiments.
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TNP #42 - Combustion Gas & Emissions Analyzer E1500 (O2, CO, CO2) Repair, Teardown & Experiments
11.3K views
November 18, 2023 2:24 PM
In this episode Shahriar explores the technology behind combustion gas analyzers. These instruments are capable of measuring the concentration of various gasses such as O2, CO, CO2, NO2, SO2, etc. The particular unit shown in this video (E-Instruments E1500) is capable of holding two sensors.
The end-of-life Oxygen sensor is replaced to bring the unit back to life. The teardown of the instrument as well as the faulty Oxygen sensor are presented along with Raman chemical analysis of the sensor electrolyte. The biproduct of a burning candle as well as a HotHands hand warmer are analyzed using the instrument.
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