YouTube Feed

The Signal Path 129K

TSP #259 - HAROGIC SAE-200 Real-Time 20GHz Portable Spectrum Analyzer Review, Teardown & Experiments

The Signal Path 11.9K views 24 hours ago

614 52

In this episode Shahriar takes a detailed look at the "pocket-sized" HAROGIC real-time 20GHz spectrum analyzer. With its 100MHz of analysis bandwidth and FPGA based signal processing, it is both powered and operates from USB-C ports:

https://rf-instruments.eu/products/sa-series/sae-200/

This review is organized as follows:

00:00 - Introductions
00:36 - Instrument overview, ports and interfaces
02:09 - Performance metrics & data-sheet details
05:39 - Complete teardown with analysis of all RF & digital boards
18:23 - Overall instrument architecture, signal & data paths
19:14 - GUI overview, purity, phase noise measurement, front-end & dynamic range
25:17 - Spurious tone, spectral purity & harmonic rejection in sweep modes
28:18 - Third order intercept, input linearity, IM3 measurement & optimization
32:10 - Real-Time mode, frequency hopping detection, plot persistence & spectrogram
35:58 - AM modulation, pulse/power detection & triggering modes
39:25 - I/Q streaming mode, modulation analysis, power versus time & I/Q versus time
47:49 - Additional features & API interface benefits
48:31 - Concluding remarks

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #258 - TEGAM AVM-2000 100nV - 1000V Null Detector / Nanovoltmeter Repair, Teardown & Experiments

The Signal Path 14.3K views March 8, 2025 4:50 PM

1K 88

In this episode Shahriar takes a look at a faulty PPM (TEGAM) Null Detector. With its massive dynamic range (10 orders of magnitude!) this instrument is capable of nano-Volt range measurements. Unfortunately the unit is faulty and does not display or measure anything at the input.

The unit requires a battery for operation (6V Lead-Acid) which can be bypassed by using a 7.4V LiPo battery. The unit powers on and the power supply section is fully functional. Detailed block diagrams and schematic analysis of the unit is discussed during the video.

The analog front-end is also verified to be functional through internal measurements and although there is digital communication between the various internal modules, the ADC only transmits a fixed (faulty) data sequence to the front-panel. The fault is traced to be a corrupted firmware which the manufacture does not agree to share.

Thanks to a helpful internet friend, firmware from a working unit is extracted and compared with the faulty instrument. It becomes clear that the corrupted FLASH memory is responsible. After transferring the calibration coefficients to the modified new firmware the unit comes back to life! Several measurements showcase the units capabilities and functionality.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #257 - Siglent SNA5000A 8.5GHz 4-Port VNA Mixer & TDR Application Review & Experiments (II)

The Signal Path 9.9K views March 2, 2025 11:49 PM

497 30

In this episode Shahriar continues the review of the Siglent SNA5000A series vector network analyzer. You can also watch the Part 1 review & teardown of this instrument:

https://youtu.be/6vHX0moZUFg

The Siglent SNA5000A continues to receive new features and upgrades:

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

This review is organized as follows:

00:00 - Introductions
02:12 - Scaler Mixer Measurement application & setup
07:33 - Mixer s-parameter & power calibration routines
11:14 - I/Q down & up-converter frequency response characterization
16:01 - Power sweeps and conversation gain implications
19:32 - Frequency doubler measurement setup & characterization
23:07 - TDR measurement application, setup & calibration
26:24 - Characterization of a SATA backplane differential channel
29:13 - Eye diagram plots, data-rate, PRBS & mask setup
32:23 - Equalization, pre-emphasis, jitter & CTLE
36:10 - Concluding remarks

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #256 - Mysteries of Optical HDMI Cables - Tutorial, Teardown & Analysis of Inexpensive Optics

The Signal Path 47.3K views January 29, 2025 2:32 PM

2.6K 185

In this episode, Shahriar takes an in-depth look at the design and architecture of optical HDMI cables, which significantly extend the reach of traditional HDMI 2.0 twisted-pair copper links at a low cost.

The fundamentals of HDMI high-speed data transmission are explored, with a focus on the TMDS (Transition Minimized Differential Signaling) standard. The challenges of transitioning from twisted pairs to optical lanes are examined, highlighting the role of VCSELs and PIN photodiodes. Optical modules are analyzed in detail, emphasizing free-space optics and optical confinement techniques used with lasers and detectors. The received high-speed lane's eye diagram is captured, and the VCSELs' optical wavelength is confirmed to be 850 nm.

Additionally, the TX (driver) and RX (TIALA) chips are inspected under a microscope, revealing the VCSEL and photodetector arrays. The overall electronic architecture is then discussed in greater detail.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #255 - Terahertz Material & Dielectric Characterization - EM Labs 330GHz Fabry-Perot Resonator

The Signal Path 19.7K views January 19, 2025 5:25 PM

1.1K 53

In this episode Shahriar takes a look at a terahertz characterization technique using a Fabry-Perot resonance chamber made by EM Labs:

https://www.emlabs.jp/en/1-8-fpr.php

The chamber is able to measure dielectric constant and loss tangent with remarkable accuracy and prevision, ideal for materials with tan δ (Df) of 0.01 or less. This tutorial and review video is organized as follows:

00:00 - Introductions
00:45 - Dielectric Constant theory, equations and practical importance
04:54 - Measurement techniques using S-Parameters and resonance chambers
08:16 - Fabry-Perot resonator techniques for accurate Dk & Df measurements
11:04 - THz measurement setup including Fabry-Perot resonator, Keysight Streamline VNA and VDI frequency extenders
13:36 - Design challenges and features of the EM Labs Fabry-Perot resonator
16:02 - Software setup, resonator calibration and preparations
19:22 - Preparing, aligning and measuring samples, organic PCB laminate and prepreg
23:19 - Measuring ultra-low loss materials in J-Band
24:21 - Analyzing anisotropic material properties as a function of orientation
26:27 - Concluding remarks

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #254 - X-Ray Florescence CMI900 Oxford Instruments Teardown, Repair & Experiments (Part 1)

The Signal Path 12K views December 21, 2024 4:29 PM

935 42

In this episode Shahriar takes a look at an X-Ray florescence machine. The CMI900 Oxford Instruments unit is not only capable of elemental analysis and identification, it can also measure the thickness of various coatings which is particularly interesting for electronics.

Unfortunately the already-non-functional unit has been further damaged in transit due to poor packaging. In this first video we dive into the repair of the unit and accompanying PC. The unit has several problems both mechanical & electrical and the damage to the PC hosting the unique interface software is also extensive. The teardown and repair procedures are covered in this video.

Stay tuned for the next episode where Shahriar will cover the theory of operation as well as range of measurement experiments.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TNP #53 - Ω-Source Electronically Controlled Resistance Decade Box Repair, Teardown & Experiments

The Signal Path 13.9K views November 23, 2024 4:53 PM

855 59

In this episode Shahriar takes a look at an interesting electrically controlled resistance decade box. The unit uses a large grid of latching relays to synthesize a wide range of resistance values from fixed surface mount resistors.
The unit has a faulty LCD screen which can be easily replaced. The repaired unit is calibrated using a Keithley 2002 8.5-Digit multimeter and meets is specifications. The resistance box is combined with an adjustable voltage regulator to realize a tunable voltage source with ease.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TSP #253 - Keysight 256GS/s, 80GHz Bandwidth M8199B 2-Channel AWG Overview, Teardown & Experiments

The Signal Path 25.2K views November 10, 2024 9:51 PM

1.2K 103

In this episode Shahriar takes a look at another world's first instrument: Keysight M8199B 256 GSa/s Arbitrary Waveform Generator. With over 80GHz of analog bandwidth, this high performance ARB is intended for design development at 160GBaud and above:

https://www.keysight.com/zz/en/product/M8199B/m8199b-256-gsa-s-arbitrary-waveform-generator.html

This video is organized as follows:

00:00 - Introductions
00:54 - ARB comparison, performance metrics, key parameters
03:59 - DAC design, chip layout, system level considerations, overall instrument architecture
14:42 - M8199B interfaces, detailed teardown, sub-block overview, output module analysis
30:14 - Demonstration setup, M8199B, DCA-X, 120GHz remote sampling use-case
33:29 - Software interfaces, I/Q tools, signal generation & calibration
36:29 - DCA-X eye-diagram captures, 64GBaud to 200GBaud, NRZ, PAM4, PAM8
44:09 - Keysight captured eye diagram & ultimate system performance
45:50 - Concluding remarks

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

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

The Signal Path 13.5K views October 27, 2024 6:14 PM

848 50

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.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

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

The Signal Path 15.9K views October 19, 2024 12:08 AM

1.2K 53

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!

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

TNP #52 - A Faxitron MX-20 TruFocus X-Ray Tube Teardown & Analysis

The Signal Path 10.1K views October 12, 2024 10:06 PM

831 53

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.

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...

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

The Signal Path 14.4K views October 12, 2024 7:00 PM

714 35

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

Please consider supporting The Signal Path:
https://www.TheSignalPath.com/Donate
https://www.Patreon.com/TheSignalPath

Other links:
https://www.TheSignalPath.com
https://www.Twitter.com/TheSignalPath
...