TNG Zoom Notes
This page contains miscellaneous information from discussions held during the TNG Zoom Online Meetings.
2020 June 18 - Ferrites
Ferrite Discussion Links:
The following topic on the nanovna-users forum on groups.io has some links used in the TNG ferrite discussion:
https://groups.io/g/nanovna-users/topic/measuring_ferrite_beads/35413448?p=Created,,,20,1,0,0
Some links brought up in TNG discussion:
Part I http://www.reeve.com/Documents/Articles%20Papers/Ferrite%20Beads/Reeve-Hagen_FerriteBeads_P1.pdf
Master Article list: http://www.reeve.com/RadioScience/Radio%20Astronomy%20Publications/Articles_Papers.htm
https://www.w0qe.com/Technical_Topics/coupling_between_coils.html
https://www.kn5l.net/S21adapter/
http://www.ifwtech.co.uk/g3sek/in-prac/index.htm#big31
NIST Method for Measuring Complex Permeability at Radio Frequencies
https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=30375
Keysight 16454A Magnetic Material Test Fixture Manual:
http://literature.cdn.keysight.com/litweb/pdf/16454-90020.pdf
Short circuit sample holder for measuring a complex permeability of toroidal magnetic samples:
http://przyrbwn.icm.edu.pl/APP/PDF/117/a117z522.pdf
Article on derating the choking effects of a suppression core due to DC current in the wires which pass though the core:
https://www.fair-rite.com/determining-the-effects-of-dc-bias-on-round-cable-emi-suppression-cores/
Keysight Application Note comparing measurement range of the VNA to the Impedance Analyzer instrument for high impedance measurements:
Power of Impedance Analyzer Comparison to Network Analyzer https://www.keysight.com/us/en/assets/7018-04664/application-notes/5992-0338.pdf?success=true
(To download or view, add email and click "No" in shaded box on right of screen)
The plots on page 6 highlight the limitations of using the VNA for high impedance measurements. The take away is that the VNA may have a measurement range too narrow for accurate measurement of ferrite cores used for RF chokes.
The impedance measurement motherload: Agilent Impedance Measurement Handbook https://www.keysight.com/us/en/assets/7018-06840/application-notes/5950-3000.pdf
(To download or view, add email and click "No" in shaded box on right of screen)
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From Fair-Rite:
How to Identify an Unknown Ferrite Core in your home workshop if you are a Fair-Rite Products Inc engineer working from home and doing videos.
Link to Fair-Rite Online Toroid Permeability Calculator (gives same results as video): https://www.fair-rite.com/toroid-calculator/
Measuring Balun Performance:
How the professionals measure ferrite impedance -- they use professional equipment: Agilent E4991A Impedance Meter
How to Identify an Unknown Ferrite Rod
Link to Fair-Rite Rod Permeability Calculator: https://www.fair-rite.com/rods-calculator/
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From Ferroxcube:
"Soft Ferrites - Ferrite materials Survey" https://ferroxcube.home.pl/prod/assets/sfmatgra_frnt.pdf
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From Prof Sma Ben-Yaakov:
Ferrite Beads in Power electronics - Ferrite characteristics in general and how ferrites can sometimes make things worse:
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From Anaren: Measurements Techniques for Baluns, 6 May 2005
https://cdn.anaren.com/multimedia/PDF/MeasurementTechniquesForBaluns.pdf
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From QEX: Measuring HF Balun Performance, Ron Skelton, W6WO, Nov/Dec 2010
http://www.arrl.org/files/file/QEX_Next_Issue/Nov-Dec_2010/Skelton_QEX_Nov-Dec.pdf
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Calculators and information from other sources:
Another online calculator from a different source: https://coil32.net/online-calculators/determine-toroid-core-permeability.html
GitHub Source Code for above calculator: https://github.com/radioacoustick/Coil64
Same calculator except downloadable independent versions for all OS's: https://coil32.net/download.html
"Magnetics" Handbook Chapter with good illustrations:
https://coefs.uncc.edu/mnoras/files/2013/03/Transformer-and-Inductor-Design-Handbook_Chapter_1.pdf
The Y21 Method of Measuring Common-Mode Impedance
http://k6jca.blogspot.com/2020/07/the-y21-method-of-measuring-common-mode.html
2020 June 25 - PF Sense
Brian did an excellent job in showing TNG Zoom participants many aspects of PF Sense as highlighted in the following presentation:
PF Sense Main site including support forums: https://www.pfsense.org/
Lawrence Systems YouTube page with several videos: https://www.youtube.com/user/TheTecknowledge
Reddit – https://www.reddit.com/r/PFSENSE/
Level1Techs video titled "Build a Router 2016 Q4 -- pfSense Build" : https://youtu.be/ledv33t6SNE
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Links related to other topics discussed during this TNG Zoom session:
AMSAT is at https://www.amsat.org/
Satellite Pass Website: https://www.n2yo.com/
Video on Free To Air Satellite TV Channels on Galaxy 16: https://www.youtube.com/watch?v=LstIsqpO1GE
2020 July 2 Tower Install
TNGZoom Session Notes:
Several hams participated in field day on many bands and modes
Tom NZ8M gave a presentation on an aluminum tilt tower installation. The method used a 12 winch and a nearby 15 ft tower section.
Also discussed was the falling derrick method such as http://www.n6rk.com/falling_derrick_gme/falling_derrick_gme.html or the one shown in Air Force manual 52-19, Antenna Systems, 1953.
Coast Guard Antenna Tower Manual: https://media.defense.gov/2017/Mar/29/2001723584/-1/-1/0/CIM_11000_4A.PDF
2020 July 09 - Grounding for your tower and shack
Jim Bacher, WB8VSU, and Mike Suhar, W8RKO, talked about grounding for your tower and shack, highlighting the work they did installing the grounding system at the N8GA VHF contest station.
Additional reference information on grounding from Jim WB8VSU provided during the Jan 2018 DARA monthly presentation:
Cadweld information from a November 2013 TNG meeting by Ken KM8AM:
-----==== Other Topics after grounding presentation ====-----
NanoVNA measurement techniques using the NanoSaver program: https://nanovna.com/?page_id=90
2020 July 16 - Network Analyzers 101 (plus NanoVNA demo)
Agilent Network Analyzer "Back to Basics" Theory Presentation
Presentation not available, but many slides are similar to: https://www.keysight.com/upload/cmc_upload/All/BTB_Network_2005-1.pdf
N2PK VNA Articles
Part I - HF Vector Network Analyzer - Some Measurement Examples: https://www.element14.com/community/docs/DOC-94326/l/hf-vector-network-analyzer-some-measurement-examples
Part I - HF Vector Network Analyzer - Theory of Operation: https://www.element14.com/community/docs/DOC-94327/l/hf-vector-network-analyzer-theory-of-operation
Part I - HF Vector Network Analyzer - Performance: https://www.element14.com/community/docs/DOC-94338/l/hf-vector-network-analyzer-performance
Future Parts:
Part 2 will be split into six sections:
VNA Hardware Overview and Schematic
VNA Construction Notes
VNA Power Interface Board
VNA Bridges and Calibration Standards
VNA Master Oscillator
VNA DDS Buffer and Detector Pre-Amplifier
Some VNA Experiments by Wes Hayward W7ZOI
"It all started during the Holidays when our son Roger showed us his new NanoVNA
vector network analyzers. It was so impressive that I placed an order for one of my
own a day or two later.
I already had a VNA in my lab, one designed by Paul, N2PK. Paul had built what I
believe was the first direct conversion vector network analyzer. It used a DDS
architecture with MC1496 mixers. The processing was done in a computer
attached to the hardware. The performance was outstanding up to the 60 MHz top
frequency with a dynamic range that equaled or exceeded that of some commercially
available high performance VNAs. This analyzer was never published in the
literature, but was treated extensively on line in a Yahoo-Group site, now replaced
with N2PK-VNA@groups.io." [ed. note - web URI is https://groups.io/g/N2PK-VNA ]
Experiments document is here: http://w7zoi.net/nanozoi.pdf
N2PK Archived Projects Page
N2PK's Amateur Radio Projects Page: https://www.makarov.ca/n2pk_archive/index.html
NanoVNA-H and -H4 General Information
The following is a summary of NanoVNA-H and NanoVNA-H4 performance. For up-to-date and complete performance information, please visit sellers website.
Measurement frequency: 10KHz -1.5GHz [NanoVNA-H, NanoVNA-H4]
RF output: 0dbm (+-2dbm)
Measurement dynamic range steps: 70dB (50kHz-300MHz), 60dB (300M-900MHz), 40dB(0.9G-1.5GHz) [NanoVNA-H, NanoVNA-H4]
Display: 2.8 inch TFT (320 x240)
USB type-C (cable included) CAUTION!! - DO NOT plug a USB-C charger, from a laptop, into the NanoVNA. The higher laptop charging voltage will totally damage the NanoVNA. Always use the included cable with a 5 volt (nominal) charger, maximum charging current 300mA for NanoVNA-H.
Built-in rechargeable battery, NanoVNA-H 650mAh battery ; for NanoVNA-H4, higher capacity battery is 1950mAH with max charging current of 1A at 5 volts (nominal)
Number of scanning points: 101 per sweep (more points if external NanoSaver PC software is used)
Frequency Tolerance:<2.5ppm; Frequency Stability:<0.5ppm (ppm = parts per million Hertz; e.g. @ 440 MHz Tolerance = +/- 1100Hz, Stability = +/-220Hz)
USB Type-C data cable and Type-c to Type-c cable are included
20 cm length (approx 8 to 9 inches) SMA male to male RG-174 RF cable (2 included)
SMA male calibration kit - OPEN, SHORT, LOAD (50 ohm), THROUGH (SMA female to female)
Touch screen stylus is the included guitar pick.
NanoVNA-H and -H4 model availability for models demonstrated:
-- The NanoVNA-H used in the TNG demonstration is the 2.8" NanoVNA-H, .5MHz-1.5GHz network analyzer. (Available from R&L Electronics, part number "NANOVNAH")
-- The NanoVNA-H4 also demonstrated is available and has a larger 4" screen. (Available from R&L Electronics, part number "NANOVNAH4")
Improved performance NanoVNA (S-A-A-2/NanoVNA_V2) General Information
The following is a summary of S-A-A-2/NanoVNA_V2 performance.
For up-to-date and complete performance information, please visit sellers website.
Frequency range: 50kHz - 3GHz [S-A-A-2/NanoVNA_V2]
Measurement dynamic range steps (calibrated): 70dB (up to 1.5GHz), 60dB (up to 3GHz)
S11 noise floor (calibrated): -50dB (up to 1.5GHz), -40dB (up to 3GHz)
Sweep rate: 100 points/s
Display: 2.8'', 320 x 240
USB interface: Micro USB
Power: USB, 5 volt (nominal) Maximum charge current 1A
Battery: 1950mAh lithium-ion
Maximum sweep points (on device): 201
micro-USB cable is included
For Low End model - 30cm SMA male to male RG316 RF cable (2 included)
For High End model - 30cm SMA male to male SS405 RF cable (2 included)
SMA male calibration kit - OPEN, SHORT, LOAD (50 ohm), THROUGH (SMA female to female)
Touch screen stylus is the included guitar pick.
The S-A-A-2/NanoVNA_V2 uses a similar user interface to the NanoVNA, but with a different technical architecture. The S-A-A-2/NanoVNA_V2 has the benefit of more points per sweep (201), 100 points per second sweep rate, increased measurement dynamic range, lower noise floor, and measurement range up to 3 GHz.
Note: The S-A-A-2/NanoVNA_V2 does not load the initial calibration data at startup, and does not automatically interpolate the calibration data after the user changes the frequency. User must recalibrate or recall previous calibration data after each startup and frequency change. The The S-A-A-2/NanoVNA_V2 is available in two versions from R&L Electronics: [SAA2LOWEND] and [SAA2HIGHEND] The difference between the high end and low end models is the test cable set is of higher performance in the high end version otherwise they are the same.
Comparison of measurements between the S-A-A-2/NanoVNA_V2 and an HP 8753E professional grade instrument.
NanoVNA PC Software for the different NanoVNA hardware versions
NanoVNA-H
nanovna-saver for https://github.com/NanoVNA-Saver/nanovna-saver/releases
Note: If nanovna-saver appears to be locked in a condition where start and stop frequencies are grayed out and sweeping is paused, then go to the calibration page and click reset to unlock.
NanoVNA-H4
https://github.com/NanoVNA-Saver/nanovna-saver/releases
Note: If nanovna-saver appears to be locked in a condition where start and stop frequencies are grayed out and sweeping is paused, then go to the calibration page and click reset to unlock.
S-A-A-2/NanoVNA_V2
VNA-QT software download: https://github.com/nanovna/NanoVNA-QT/releases
https://github.com/NanoVNA-Saver/nanovna-saver/releases
Note: If nanovna-saver appears to be locked in a condition where start and stop frequencies are grayed out and sweeping is paused, then go to the calibration page and click reset to unlock.
Installing and using NanoVNA-saver on Windows 10:
Download the windows-latest zip file from https://github.com/NanoVNA-Saver/nanovna-saver/releases under "assets" for any version.
Unarchive to a folder of your choice.
In the folder containing the nanovna-saver.exe, right click on nanovna-saver.exe select properties and check the UNBLOCK box then click OK.
Clicking OK will avoid the annoying message each time nanovna-saver is run.
Note: On some PCs with Windows 10, it may take a minute for the nanovna-saver GUI display to be active. Just wait for it.
You may notice that nanovna-saver screens are too wide and too tall to fit entirely on the monitor screen.
To fix this go into Windows Settings - System - Display.
Change "Scale and Layout - change the size of text, apps, and other items" from "150% (recommended)" to "100%".
Close the Settings window.
The nanovna-saver will now entirely fit in the monitor screen area, but graphics and text will be smaller.
The original display setting can be restored by opening display settings and changing back to "150% (recommended)".
NanoVNA Manuals
NanoVNA-H
http://gunthard-kraus.de/fertig_NanoVNA/English/English_NanoVNA_2020_part%201.pdf
http://gunthard-kraus.de/fertig_NanoVNA/English/NanoVNA%20H2_English.pdf
Interactive Menu Help map: https://oristopo.github.io/nVhelp/html/Menu.htm?fbclid=IwAR3U0_00-NiTBYDpX_kOCqoNRUJp8C3dSodlbhdW-lhfHT4eRcNlmxo59-Y
NanoVNA-H4
http://gunthard-kraus.de/fertig_NanoVNA/English/English_NanoVNA_2020_part%201.pdf
http://gunthard-kraus.de/fertig_NanoVNA/English/NanoVNA%20H2_English.pdf
S-A-A-2/NanoVNA_V2
User guide: https://github.com/nanovna/NanoVNA-QT/raw/master/ug1101.pdf
NanoVNA Miscellaneous Information (Forums, Source Code, etc)
Forums
(some of the info in nanovna-users below, may apply to the S-A-A-2/NanoVNA_V2 model)
NanoVNA-H and NanoVNA-H4
https://groups.io/g/nanovna-users/
S-A-A-2/NanoVNA_V2
https://groups.io/g/NanoVNA-V2
Source Code / Firmware
Don't update firmware unless you absolutely need to and know how to do it. See information in groups.io forum.
NanoVNA-H (hugen79 2.8" version)
Don't update firmware unless you absolutely need to and know how to do it. See information in groups.io forum.
Several NanoVNA-H VNAs come with firmware version (from config-version menu) of 0.2.3-2-8ac9166b with a build time of TBD.
This version is found after searching the github commit number of several developers.
The developer is Hugen79 and the firmware source for this version is at https://github.com/hugen79/NanoVNA-H/commit/8ac9166b0251dd94866cfd2d02f33f8f0cac6638
The 8ac9166b version was committed on Oct 18, 2019 by hugen79 on the NanoVNA-H github repository of hugen79.
If it is desired to stay with the Hugen79 firmware developer, the latest NanoVNA-H firmware release is here: https://github.com/hugen79/NanoVNA-H/releases/tag/0.4.5-4 version 0.4.5-4 released on Jan 18, 2020
NanoVNA-H4 (hugen79 4.0" version)
Don't update firmware unless you absolutely need to and know how to do it. See information in groups.io forum.
Several NanoVNA-H4 VNAs come with firmware version (from config-version menu) of 0.4.5.7-g57d62f2 with a build time of Jan 1, 2020 - 17:27:30.
This version is found after searching the github commit number of several developers.
The developer is AA6KL and the firmware source for this version is at https://github.com/AA6KL/NanoVNA-H4/commit/57d62f26fbe3186eb30962b150587a2f203f3727
The 57d62f2f version was committed on Dec 29, 2019 by hugen79 on the NanoVNA-H4 github repository of AA6KL.
If it is desired to stay with the AA6KL/BV4WG(Taiwan) firmware developer, the latest NanoVNA-H4 firmware release is here: https://github.com/AA6KL/NanoVNA-H4/releases/tag/v1.3 version 1.3 released on Feb 20, 2020.
If it is desired to use the release by hugen79 then find version 0.5.0 here: https://github.com/hugen79/NanoVNA-H/releases/tag/0.5.0
S-A-A-2/NanoVNA_V2
Don't update firmware unless you absolutely need to and know how to do it. See information in groups.io forum.
Firmware files are here: https://github.com/nanovna/NanoVNA-V2-firmware/releases . Download the desired firmware file to a convenient location on the PC.
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Software Tools for Updating Firmware
NanoVNA-H (hugen79 2.8" version)
Check back later.
NanoVNA-H4 (hugen79 4.0" version)
Check back later.
Linux Command line firmware update for NanoVNA-H or NanoVNA-H4
S-A-A-2/NanoVNA_V2
Before starting, check and note the firmware date and commit identifier (7 characters string under the date), using the Config-Version menus on the VNA, and match it to one of the versions on the Github releases page. The firmware is installed with the VNA-QT software (from https://github.com/nanovna/NanoVNA-QT/releases ). Also, verify that the S-A-A-2/NanoVNA_V2 operates with the VNA-QT software before attempting the firmware update.
Start the update process with the VNA-QT software closed and turn off the S-A-A-2/NanoVNA_V2. Leave the USB cable connected. On the S-A-A-2/NanoVNA_V2 device, push and hold the left push-button switch while powering-on the device with the side slide-switch. The device will have a blank lighted screen. Then, open the VNA-QT software. The VNA-QT software will recognize that the VNA is in the firmware update mode and will prompt for the firmware bin file location on the PC. Once the file is entered and selected, the firmware will upload automatically. Disconnect the USB cable and cycle power. Check the version information on the device using the Config-Version menu and verify that the date and commit identifier is correct for the version you selected for the update.
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Touchstone File Specification
NanoVNA and many other devices use the Touchstone file format for input and output data
http://www.ibis.org/touchstone_ver2.0/touchstone_ver2_0.pdf
NanoVNA YouTube Videos
#502 NANOVNA Demystified - NanoVNA input bridge and mixer and how they contribute to the measurement, in general
Why a VNA needs to be calibrated | how to calibrate a nanoVNA W2AEW
NanoVNA (rev3.4): Correct 2-Port Calibration KB3WFQ
How to use the NanoVNA to sweep / measure an antenna system's SWR and optimize its tuning W2AEW
How to use the NanoVNA to measure a low-pass filter W2AEW
Use NanoVNA to measure coax length - BONUS Transmission Lines and Smith Charts, SWR and more W2AEW
#77: The Reference Plane W0QE
#78 Building VNA Calibration Loads W0QE
#89: VNA Calibration Through a Cable - What Can Go Wrong W0QE
#90: Building VNA Calibration Loads - Revisited W0QE
#95 Three Methods to Measure Impedance with the NanoVNA (and SimSmith) W0QE
#96 Can You Measure a 10k Impedance at 100MHz with a VNA? W0QE
https://youtu.be/0JglLhrisOs and companion web articles: http://w0qe.com/Measuring_High_Z_with_VNA.html and http://w0qe.com/Measuring_RF_Impedances.html
TTT320 NanoVNA V2 Review and Comparison to Original NanoVNA TomTekTest
NanoVNA V2: Measuring DIY Microstrip L-Band LNAs KB3WFQ
#317: NanoVNA Port Extension using the Electrical Delay setting W2AEW
In-Circuit Antenna Verification - Copper Mountain VNA probing PCB antenna and matching hints - Port Extension demo
2020 July 23 - Open Topic Discussion IQ Processing
How does IQ modulation and Demodulation work?
A wikipedia page shows rhe basic concept -- https://en.wikipedia.org/wiki/In-phase_and_quadrature_components
Legacy Hewlett-Packard Java Demos were shown and are not available on the web. Here is some modern Keysight info -- https://www.keysight.com/upload/cmc_upload/All/IQ_Modulation.htm
A different way of viewing IQ signals -- https://www.pe0sat.vgnet.nl/sdr/iq-data-explained/
Youtube tutorials on IQ Modulators and Mixers W2AEW:
#170: Basics of IQ Signals and IQ modulation & demodulation - A tutorial https://youtu.be/h_7d-m1ehoY
#171: IQ Signals Part II: AM and FM phasor diagrams, SSB phasing method -- https://youtu.be/5GGD99Qi1PA
#167: How a Diode Ring Mixer works | Mixer operation theory and measurement -- https://youtu.be/junuEwmQVQ8
#83: Basics of RF Mixers in Radio Receivers / Mixer Tutorial / Frequency Conversion -- https://youtu.be/Mm7WfVzr1ao
#260: RF Diode Mixer LO Drive Level & Conversion Loss | 1dB Compression | Distortion -- https://youtu.be/GvadQpkZ8l0
#262: IQ Modulator Basics: Operation, measurements, impairments -- https://youtu.be/GvadQpkZ8l0
IQ Radio Example - Tiny Pico Radio by NA5Y https://github.com/thaaraak/Tinypico-Radio
TinyPICO Radio Part 1 - Micropython and the Local Oscillator -- https://youtu.be/y6PFM3ab1Qs
TinyPICO Radio Part 2 - Tayloe Detector and Testing -- https://youtu.be/iwBk3jIxszI
Tayloe detector Paper "Ultra Low Noise, High Performance, Zero IF Quadrature Product Detector and Preamplifier" by Dan Tayloe: http://www.norcalqrp.org/files/Tayloe_mixer_x3a.pdf or https://pdfs.semanticscholar.org/a9f9/455983c0dd925c7ca0ad4a54435747572b3f.pdf
Full TinyPICO Radio Playlist NA5Y-- https://www.youtube.com/playlist?list=PLsMaN1bGWyny-iAMIHsq2s4dtAXkjOX_F
2020 Aug 20 - Minimizing Effects of Aluminum Antenna Corrosion
ARRL Fighting Antenna Corrosion - Tip on attaching copper wire to aluminum: http://www.arrl.org/files/file/QST_Apr_1993_p24-26.pdf
ARRL article on Galvanic Corrosion: http://www.arrl.org/galvanic-corrosion
ARRL Anti-Oxident Product List: http://www.arrl.org/files/file/Technology/tis/info/pdf/Anti-OxidantGrease.pdf
Krylon Clear Acrylic Spray is mentioned by K3PGP in ARRL link to dxmaps blog excerpt on "Aluminum oxidization & protection of Yagi elements": http://www.dxmaps.com/discuss/aluminium.html
Spray Coatings that may delay aluminum corrosion:
Krylon Acrylic Crystal Clear coating 1303 spray can mentioned by K3PGP in ARRL link to dxmaps blog excerpt above: https://www.krylon.com/products/crystal-clear-acrylic/
Krylon Industrial ACRYLI-QUIK ACRYLIC LACQUER, Clear, Part No. K01301A07 https://www.krylonindustrial.com/product/acryli-quik-acrylic-lacquer/ Krylon 1301 also mentioned by K3PGP as possibly better.
Sprayon EL600 Clear Electrical Lacquer (acrylic) https://www.paintdocs.com/docs/webPDF.jsp?SITEID=SO&doctype=PDS&prodno=S02000000&lang=2 This one mentioned because of electrical properties listing.
Sprayon EL2000 Clear Electrical Lacquer (acrylic) Sealer https://www.sprayon.com/product/clear-electrical-lacquer-sealer/ This one mentioned because of electrical properties listing.
Here is correspondence between John, K3PGP and Krylon Consumer Affairs on the defference between acrylic lacquer sprays of up to the date of correspondence April 6, 1999:
">Dear John," [K3PGP]
">
>The product you were using 25 years ago and the Krlon Acrylic Clears today do not differ very much at all. Although the solvents have changed slightly, the resin system is virtually the same. After contacting the lab I found that when the product has dried, the paint film is the same.
>
>Thank you for your inquiry,
>
>Consumer Affairs" [Krylon]
More than 20 ways to match to a single impedance - https://youtu.be/HDsMsCMvZCU
2020 Aug - TBD
TBD
Keywords: Zoom Notes links