TSP #172 – Tektronix 6-Series 4-Channel 25GS/s 8GHz MSO Review, Teardown & Experiments (Part 1)

In this episode Shahriar reviews the top-of-the-line Tektronix 6-Series Oscilloscope:

https://www.tek.com/oscilloscope/6-series-mso-mixed-signal-oscilloscope

This 4-channel instrument offers 8-GHz of bandwidth at 25GS/s on all channel independently. Tektronix has made great strides in offering low-noise front-end custom ASICs combined with hardware digital down-conversion built into the core of the 6-Series. This enables advanced triggering across in both time and frequency domains as well as multi-domain correlated measurements.
This review is organized as follows:

00:00 – Introductions
01:42 – Instrument design, front and back panels
03:34 – Full acquisition board teardown, analysis and architecture
18:11 – PLL Experiment: Spectrum View, advanced triggering, PLL characterization and debugging
38:33 – Backplane Communication: Jitter analysis, eye diagrams, jitter composition, cross-talk
49:24 – Concluding remarks

The Signal Path
http://www.TheSignalPath.com
http://www.YouTube.com/TheSignalPath
http://www.Patreon.com/TheSignalPath

TSP #171 – Signal Hound SM200C/B 20GHz Real-Time Spectrum Analyzer Review, Teardown & Experiments

In this episode Shahriar reviews the long awaited Signal Hound SM200C/B Real-Time 100kHz – 20GHz Real-Time Spectrum Analyzer:

The SM200C is a high-performance spectrum analyzer and monitoring receiver with a 10 Gigabit Ethernet SFP+ port, enabling the SM200C to communicate with a PC over long distances using a fiber optic cable. Designed for remotely-located accurate RF data analysis at the lowest cost possible, the SM200C features:

160 MHz instantaneous bandwidth I/Q streaming over 10GbE
SFP+ port for fast, long-distance communication with a PC using an optic cable
Device control and data transfer occurs via SFP+ connection, not USB
Tunes from 100 kHz to 20 GHz
Sweeps at 1 THz/sec at 30 kHz RBW
110 dB of dynamic range
Ultra-low phase noise
GPIO port antenna switching
The SM200B offers a USB 3.0 PC interface with 40MHz of instantaneous I/Q streaming. Furthermore, the SM200B includes a full 2-second of internal memory at 160MHz of capture bandwidth which an be accessed through the API.

The review is organized as follows:

00:00 – Introduction
00:49 – Overview, build quality and detailed specifications
05:51 – Full teardown, analysis and system architecture
18:00 – 10GbE PC interface using M.2 Key to PCIe converter
19:22 – Experiment #1: FMCW signal analysis, GUI overview & 160MHz capture capabilities
31:33 – Experiment #2: Interfering hunting, FM-versus-time, frequency hopping & advanced triggering
41:32 – Experiment #3: Digital demodulation, phase-noise & equalization
46:02 – Other GUI capabilities, mask & EM compliance, API
47:20 – Concluding remarks

http://www.TheSignalPath.com
http://www.YouTube.com/TheSignalPath
http://www.Patreon.com/TheSignalPath

TSP #170 – Is 5G Dangerous?

In this episode Shahriar discusses some of the concerns surrounding the 5G Cellular Wireless Technology. It is important to understand the technology and the history of why 5G is unique in some ways compared with 4G LTE.

The evolution of cellular wireless technology is briefly discussed alongside with dangers of electromagnetic radiation across the entire spectrum. 5G mm-wave beam-forming technology is explored and the actual RF power levels at ground level is computed. Finally some questions about science and technology are discussed.

http://www.TheSignalPath.com
http://www.YouTube.com/TheSignalPath
http://www.Patreon.com/TheSignalPath

TSP #169 – Upgrade & Experiments with an Agilent 8445B Auto Preselector – Giveaway! (April 2020)

In this episode Shahriar retrofits a vintage HP 8445B Auto Preselector for testing and characterization of high-performance data converters and oscilloscopes. The Preselector is in essence an electronically tunable band-pass filter with exceptional tuning range and quality factor.

After examining the schematic and block diagram of the instrument the unit is equipped with additional potentiometer, low-band, high-band switch and a voltmeter LCD screen which displays the center frequency. The modifications are applied to the front panel as well as internal circuitry to enable manual control of the preselector without the need for any external devices.

The modified instrument is used to measure the harmonic improvement of a 20GHz synthesizer. Several oscilloscopes are then characterized using the new preselector to determine the absolute performance of their internal data converter.

Finally, it is also time for a new giveaway! A brand new Keysight DSOX1102G scope! Patreon supporters are automatically enrolled. The giveaway is open to all other viewers as well. Just leave a comment on YouTube to be entered.

http://www.TheSignalPath.com
http://www.YouTube.com/TheSignalPath
http://www.Patreon.com/TheSignalPath

TSP #168 – Teardown & Repair of an Agilent E8257D 250kHz – 31.8GHz PSG Analog Signal Generator

In this episode Shahriar repairs an Agilent E8257D PSG Analog Signal Generator generously loaned by AllTest. Please visit their website for all your measurement, calibration and service needs:

sales@alltest.net
https://alltestchambers.net
https://alltest.net

The instrument does provide an RF output signal. However, there is also a large DC offset voltage present at the output RF port which changes depending the frequency band. The DC voltage is present even when the output RF signal is disabled. Furthermore, the OCXO of the instrument is defective and does not produce a 10MHz output signal.

The block diagram of the PSG is examined in details with emphasis on the final attenuator, coupler and doubler RF decks. Interestingly enough the output offset is traced all the way back to the Modulator Filter block. The teardown of the module reveals a series of PIN diode switches and after some investigation the fault is traced to a damaged PIN diode on the sub-3.2GHz path. Since the diode can’t be easily replaced, the control voltage to the diode is disabled instead which removed the DC offset problem.

The OCXO teardown reveals that during a prior repair, the oscillator module has been damages and torn off the PCB. New pins are added to the oscillator module which returns the crystal back to working condition. The performance of the PSG is verified using a spectrum analyzer and frequency counter.

http://www.TheSignalPath.com
http://www.YouTube.com/TheSignalPath
http://www.Patreon.com/TheSignalPath