TSP #41 - Teardown and Repair of an Agilent E4433B ESG-D 4.0GHz Synthesized Signal Generator (2014)
41.4K views
December 22, 2014 3:00 AM
In this episode Shahriar repairs an Agilent E4433B ESG-D Synthesized Signal Generator. This 4GHz unit shows the “UNLEVEL” error for all frequencies and at all output power levels. After a close look at the system block diagram the fault is traced to the main Output RF board.
The Output RF board is equipped with various amplifiers, electronic attenuators, I/Q mixers, heterodyne paths and final PA. By using soldered SMA cables to various points in the signal path, the fault is traced to an internal amplifier chain which is likely made of a MESFET or JFET transistor. Since this part is obsolete, an RFMD GaAs hybrid amplifier is used in its place. The biasing network and matching networks need to be modified to accommodate this change. The repaired unit is then verified for functionality and performance by measuring a QAM constellation output signal.
The Signal Path Blog
http://www.TheSignalPath.com
TSP #40 - Review and Comparison of Siglent SDG5162 and Rigol DG4162 Arbitrary Waveform Generator
23.9K views
December 7, 2014 2:14 AM
In this episode Shahriar compares the performance and features of the Siglent SDG5162 and Rigol DG4162 Arbitrary Waveform Generators. Siglent has recently opened a new North America office which would certainly help them bring their instruments to the US more quickly and provide better local customer and sale support.
The Siglent SDG5000 teardown is presented. Aside from various GUI features of these two units, the THD, phase noise and maximum output power of each unit is measured. The ability of the Siglent generator to produce 12ns pulse width independent of the output frequency is also presented with some practical applications. Finally the Easy Wave application us is used to generate some custom waveforms.
The Signal Path
http://www.TheSignalPath.com
TSP #39 - Teardown and Repair of an Agilent 33250A Function and Arbitrary Waveform Generator
37.4K views
November 24, 2014 2:38 AM
In this episode Shahriar repairs an Agilent 33250A function and arbitrary waveform generator which does not power on. The unit is equipped with a soft power switch which might be responsible for the fault. After a brief look at the unit’s constructions, the fault is traced to a few possible locations.
The schematic of the soft power circuitry is presented and the internal switching power supply is closely examined. After the fault is located, the repair is presented. The block diagram and operation of a current mode DC-DC switching IC is also presented.
The Signal Path
http://www.TheSignalPath.com
TSP #38 - Teardown, Upgrade and Experiments with a Verity Visible Wavelength Monochromator
30.6K views
November 21, 2014 2:52 AM
In this episode, Shahriar upgrades a Verity visible wavelength monochromator model EP200Mmd to be able to perform automatic scans. The instrument is retrofitted with a stepper motor and a microcontroller which performs wavelength scanning between 225nm to 875nm. The signal from the internal photomultiplier is sampled by the microcontroller and wirelessly sent to the computer. Matlab is used to plot the wavelength response.
The principle operation of a monochromator is thoroughly reviewed starting with the grating mirror behavior. The operation of the photomultiplier is also described. Various mechanical and electronic of the upgraded system is also shown. The presented slides can be found on The Signal Path website.
The Signal Path
http://www.TheSignalPath.com
TSP #37 - Tektronix RSA306 USB Real-Time Spectrum Analyzer Review and Experiments
62.9K views
November 4, 2014 9:00 AM
In this world exclusive episode, Shahriar takes a close look at the all new Tektronix Real-Time USB Spectrum Analyzer. The RSA306 has an RF bandwidth from 9kHz to 6.2GHz with a real-time analysis window of 40MHz. While being entirely powered form a single USB 3.0 interface, it provides a 100% Probably of Intercept for any signal event of at least 100us in duration. The RSA306 is compact, lightweight and shock resistant. At the same time Tektronix has made its Signal-Vu PC software with 17 measurement capabilities free and significantly reduced the price of other Signal-Vu advanced applications!
The SFDR, linearity, noise floor and phase noise of the instrument are all measured and presented. The unit is then used to capture and analyze an intermittent RF interference, analyze and demodulate an RF FM signal using an antenna as well as demodulation a 256-QAM signal with -65Bm of total power.
The Signal Path
http://www.TheSignalPath.com
