TSP #212 – Siglent SNA5000A 8.5GHz 4-Port Vector Network Analyzer Review, Teardown & Experiments (I)

August 28, 2022 No comments

In this episode (Part 1) Shahriar presents a detailed review of the Siglent SNA5000A series vector network analyzer. The Siglent SNA VNA has a frequency range of 9 kHz to 8.5 GHz, with 2- and 4-port models available. Designed to give you instant insight into scattering, differential, and time-domain measurements. Siglent VNAs enables measurements of the Q-factor, bandwidth, and insertion loss filters and feature impedance conversion, movement of measurement plane, limit testing, ripple test, fixture simulation, and adapter removal/insertion adjustments. There are five sweep types: Linear-Frequency, Log-Frequency, Power-Sweep, CW-Time, and Segment-Sweep mode. SNA5000A VNAs also support scattering-parameter correction of SOLT, SOLR, TRL, Response, and Enhanced Response for increased flexibility in R&D and manufacturing applications:

https://siglentna.com/vector-network-analyzer/sna5000a/

This (Part 1) of the review is organized as follows:

00:00 – Introductions.
01:02 – Instrument overview, design, user & RF interfaces.
04:27 – Detailed teardown, architecture, RF design & VNA board reverse engineering.
18-21 – Calibration, E-Cal compatibility, built-in procedures, initial GUI overview.
22:12 – High rejection filter characterization, pushing the dynamic range limit, port-to-port isolation, IF BW, filtering & averaging.
28:28 – Characterizing active devices, measurement topology, differential & common-mode responses, power control, waveform comparison, phase & magnitude response.
39:07 – Sweep types, power sweep, compression measurements, non-linear DUT characteristics, impedance & Smith charts.
44:12 – VNA as RF synthesizer, CW generation, tone purity & power accuracy.
45:26 – Concluding remarks.

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

TSP #211 – Keysight 20GHz MXG Analog RF Signal Generator Teardown, Repair & Analysis (Part 1)

August 20, 2022 No comments

In this episode Shahriar investigates a failed Keysight MXG RF generator. The instrument shows UNLEVEL for frequencies above 10GHz. The measurements confirm that the instrument fails to achieve the desired output power. The block diagram of the synthesizer is examined in details and potential failure points are identified.
The teardown of the instrument and various components are also presented. A detailed description of the multiplier unit is shown along with the PCB X-Ray. Measurements confirm the failure of an Agilent-branded component (doubler + amplifier module). The repair has to be paused for now until a replacement component is sourced.

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

TNP #20 – Stanford Research Systems SR830 DSP Lock-in Amplifier Teardown, Repair & Experiments

August 4, 2022 No comments

In this episode Shahriar takes a look at a SRS SR830 DSP Lock-in amplifier. The repair of the instrument is fairly simple and provides a quick look at the internal construction of the unit.
The instrument is then used for characterizing nonlinearities of a pair of matched diodes in large-signal operation. A Tektronix 4-Series is also used alongside the SR830 in DDC mode to show the harmonic behavior of the DUT in frequency domain. The SR830 is able to discern extremely small variation in temperature between the diodes and the resultant 2nd order harmonic changes in both amplitude & phase.

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

TSP #210 – Going off-grid! BigBattery RHINO 48V, 14kWh LiFePO4 Battery Review & Experiments

July 31, 2022 No comments

In this episode Shahriar takes The Signal Path Lab off-grid! The BigBattery RHINO 48V LiFePO4, 276Ah, 14kWh is combined with a Growatt SPF 6000T inverter to provide 240V split-phase power to the house.

You can see the kit used in this video using this untracked, direct link to BigBattery.com:

https://bigbattery.com/products/48v-off-grid-home-rhino-system/

The review of the battery is organized as follows:

00:00 – Introductions & considerations.
01:33 – BigBattery offerings, battery configurations, battery chemistry, specifications, warranty, etc.
05:51 – Battery construction quality, connector & fuse design, mobile cart, attachment options.
07:50 – Provided battery cable with Anderson connector, ratings, quality.
08:14 – Built-in LCD screen, GUI & BMS access from the battery, phone app & BMS configuration.
11:36 – Battery protection, BMS under small loads, BMS disconnect behavior, power reporting.
16:08 – Off-grid setup, Growatt inverter wiring & interfaces, transfer switch & AC access.
18:28 – Benefits of a boiler setup for battery backup operation.
18:59 – Ensuring correct earth-ground & neutral wiring of the backup system.
19:52 – Going off-grid! House power measurements, battery discharge behavior.
21:27 – Battery charging behavior, balancing, charging battery to maximum level, charge waveform.
22:44 – Concluding remarks.

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

TSP #209 – Teardown, Repair & Analysis of an Agilent 83752A 10MHz – 20GHz RF Synthesized Sweeper

July 22, 2022 No comments

In this episode Shahriar takes a close look at an HP 83752A which shows no signs of life. The power supply of the instrument does not produce standby or any other output voltages. The power supply is examined and the startup circuitry is at fault. The problem is traced to a bad startup capacitor for the primary PWM controller. A replacement resolves the issue and the instrument powers on.
The instrument however has other issues. An UNLOCK condition is displayed and further testing shows that the frequency output of the instrument below 2GHz is unstable. The overall block diagram of the unit is presented and the fault is logically traced to a potential problem with the reference 100MHz of the hetrodyne block. An X-Ray of the board allows us to reverse engineer the final output amplifier and a faulty NPN is located. A replacement resolves the UNLOCK condition and the instrument is fully functional.

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

« Older Entries   Recent Entries »