TSP #252 – Mini-Circuits 37dBm 1GHz Power Amplifier Repair, Teardown & RF Characterization Tutorial

In this episode Shahriar takes a look at benchtop power amplifier unit from Mini-Circuits. The amplifier operates from 0.5 – 1000MHz and can provide over 4W of saturated output power. The amplifier is not functional and provides no gain or output power.
The teardown reveals the “hand-made” nature of the multi-stage RF amplifier inside. Although the internal power supply is functional, none of the five internal RF stages have any supply voltage. The problem is traced to a broken small fuse soldered to the main PCB. A new fuse holder is installed.
The amplifier is extensively characterized for frequency response, Psat, P1dB, OIP3, NF as well as efficiency. Details of measurements techniques for each parameter is discussed in details.

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TSP #251 – Agilent 50GHz PSA (E4448A) Spectrum Analyzer Teardown, Repair & Experiments (Part 1)

In this episode Shahriar takes a look at the faulty Agilent 50GHz spectrum analyzer which does not power on. After tracing the issue and restoring the bootting sequence, it is clear that the instrument has several other issues. The attenuator step calibration failure is addressed which clears all startup errors. However, the instrument still does not measure some frequency bands correctly which points to a failure in the band-selection & mixer assembly. We will have to return to this instrument again in Part 2!

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TNP #52 – A Faxitron MX-20 Micro-Focus X-Ray Tube Teardown & Analysis

In this episode Shahriar tales a close look at a defective X-Ray tube from a Faxitron MX-20 x-ray machine. The tube overloads the high-voltage power supply and does not produce any x-ray. The protective mold is removed from the tube to reveal its inner design. The glow of the heating element is also shown.

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TSP #250 – Tektronix TriMode Active 10GHz (TDP7000) Probe/Tips Review, Teardown & Experiments

In this episode Shahriar takes a close look at the TDP7000 Series TriMode Probe and accompanying active probe tips.

https://www.tek.com/en/datasheet/trimode(tm)-probe-family-1

The review is organized as follows:

00:00 – Introductions
01:23 – TriMode principle of operation
02:37 – Using the 2.92mm/SMA 50-Ohm probe tip adapter, single-ended, differential, common-mode measurements
10:39 – Solder-in flexible probe tip, measurements of a PCI-E 2.5Gbps data stream, eye diagrams, jitter analysis
20:22 – Differential browser use-case, in-circuit synthesizer measurements, frequency domain analysis
25:47 – Detailed look at the flexible, solder-in probe tip, front-end design, integrated circuit reverse engineering
35:58 – Concluding remarks

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TNP #51 – Thorabs PM320E Dual Channel Optical Power & Energy Meter Teardown, Repair & Experiments

In this episode Shahriar takes a look at faulty Thorlabs optical power meter which has been scored from eBay at a very low price. The listing shows the screen with a white background without any text. Upon close inspection however, it is clear that the screen contrast is the problem. The fault is traced to a basic voltage setting problem (230V versus 115V) which was causing the +/-15V supplies to be significantly under biased.

With the screen issue resolved, the unit is paired with two C-series optical detectors. Various laser power measurements & experiments demonstrate the full functionality of the unit.

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