In this episode Shahriar continues his journey with upgrading the Zeiss microscope. The microscope is now entirely motorized including the XYZ axis. This, combined with a high-quality Nikon DLSR allows the creation of some extraordinary focus stacked imaged. The interface between the microscope & DSLR is handled through an LMScope adapter:

https://www.lmscope.com/en/produkte_en.html

The microscope is controlled via a custom GUI which manages all of the microscope functions as well as a fully automated focus stacking routine.

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In this episode Shahriar dives into the detailed operation of a HeCd laser system. The laser head sub-components and principle operation is discussed as well as the teardown of the power supply and its primary sections. Various spectral measurements are performed on the laser output as well as the non-coherent emissions from the main laser cavity.

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In this episode Shahriar takes a look at a faulty E5052A signal source analyzer. Despite their age, these signal-source analyzers are highly sought after and very valuable. Although the analyzer can measure phase noise, it reports the incorrect input signal power across frequency. Initial assessments shows that the reported measured power varies wildly across the band.
The system block diagram is shown and principle operation of the instrument is described. From there, a few measurements are devised to verify the operation of the detectors, power splitter, etc. The problem is traced down to a broken connector on a custom resistive power divider. After the repair, the instrument reports the correct power. The overall performance is verified by measuring the phase noise of a Signal House PNCS-1 using cross correlation techniques.

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In this episode Shahriar quickly repairs a faulty Fluke 732A DC Reference Standard. Although the unit does produce a good 10V and 1.018V output, the 1V output shows no voltage at all. A close examination of the schematic shows that the 1V output is derived through a resistor divider from the 10V source.
Since no resistance can be measured from the 1V to any of the other ports, it is suspected that the failure is caused by a broken connection behind the front panel. The connection is corrected and the unit produces all desired output signals.

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In this episode Shahriar repairs an HP 87421 power supply in order to revive a HP 83017A 0.5-26.6GHz Microwave System Amplifier. The power supply has multiple bad capacitors which can be readily exchanged. An X-ray of a bad versus good capacitor is also shown. A custom cable must be made and the pinouts of each module should be revers engineered.
The amplifier successful powers on and various performance metrics are measured. S-parameters, noise figure, PSAT, OIP3 and detector are all measured and verified. The instrument used are the Keysight FieldFox, Junkosha RF cables, R&S NRP power sensor, R&S SMB RF Vector Generator and R&S ZNL20 real-time spectrum analyzer / network analyzer hybrid.

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