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The timeline for submission of papers and presentations has been extended to March 17th.

When using my NanoVNA to adjust length of a 20m hamstick, the readings kept changing depending on what the NanoVNA was sitting on (truck hood, pelican case, my thigh, or in my hand). How do I get a reliable reading that I can count on for a properly adjusted antenna? Thanks, Coyote

My NanoVNA H4 is not operating properly, I'm about to buy a new one. Is R&L the place to get a real model? Mikek

With the ADC detection button, you can set multiple shortcut keys, such as entering DFU mode, taking screenshots, pausing scanning, and so on. Because of these menus, I need to click several times to find the location, which is very inconvenient for me, so I thought of setting this shortcut key to enter the corresponding menu with one click. I guess this should be a very useful feature.

My first VNA SAA-2N in 2020, love the large SO-259 connectors instead of SMA connectors. I notice that my touch screen is not working right. Hit display nothing happens, trace doesn't do anything either. Can this be corrected. I purchased a new NanoVNA F V2 that was 3x what I paid for the SAA-2N. I don't like the menu layout or the SMA connectors. The 2 RF cables are so stiff they hardly bend, afraid using them I will break the SMA connector on the Nano. What is the difference between the F model and the H model. Cause I may return this F with these 2 stiff RF cables

Sad news: https://www.owenduffy.net/ (mostly electronics) is no longer available. regards Fred

Yeah, but there is the problem that the resistances are small (compared to impedance), so things which have “percentage uncertainty” (which the VNA uses) will be tough. It might help to look at the uncertainty of your measurement (that is, how the calculation of impedance is done). It may be that your measurements are within the uncertainty of each other. Z = Zo * ((1 + Γ) / (1 - Γ)) Gamma, here, is basically the ratio between the forward and reflected voltages. Which are complex numbers, where the uncertainties are roughly equal in I and Q.

I built this fixture some time ago. It makes measuring chokes, baluns and ununs common mode very simple. The SOL(T) CAL loads are built onto the PCB. My interest in common mode reduction now lies in VHF and UHF where this jig will not function because of lead lengths. All mounting hardware (except the banana sockets) has been replaced with stainless steel. https://electronics.halibut.com/product/common-mode-current-choke-test-rig/ $50 includes USPS shipping in the USA. Regards, Dale W4OP

I report with a heavy heart, confirming your suspicions. The hobby has lost one of its greatest on-line resources. Read on. Ed McCann AG6CX

I've tried installing DiSlord firmware version 1.2.40 on my NanoVNA-H4, but it seems to "brick it" Going back to 1.2.29 works. Ideas as to why 1.2.40 doesn't work? I've tried uploading it with the NanoVNA app and the DFU demo program. Same results with both. 73 Stan KM4HQE

Are there operating instructions for this VNA? The way it display data is different compared to my earlier and much smaller Nanovna. Dave

Screwed up the title. It pays to read before posting.

Southeastern VHF Conference 2025 Announcement & Call For Papers Quality Inn, 3095 Wilma Rudolph Blvd, Clarksville, TN 37040 April 4th and 5th, 2025 Papers and presentations are solicited on both the technical and operational aspects of VHF, UHF and Microwave weak signal amateur radio. Some suggested areas of interest are: ? Transmitters, Receivers, Transverters ? RF Power Amplifiers, RF Low Noise Preamplifiers ? Antennas ? Construction Projects ? Test Equipment and Station Accessories ? Station Design and Construction ? Contesting, Roving, DX-peditions ? EME, Propagation (Sporadic E, Meteor Scatter, Troposphere Ducting, etc.) ? Digital Modes, Digital Signal Processing (DSP), Software Defined Radio ? (SDR) Amateur Satellites, Amateur Television In general papers and presentations on non-weak signal related topics such as FM repeaters and packet will not be accepted but exceptions may be made if the topic is related to weak signal. For example, a paper or presentation on the use of FM simplex in contests or on the use of APRS to track rovers during contests would be considered. Formats: All submissions for publication in the proceedings should be in Microsoft Word (.doc or .docx) formats. Submissions for presentation at the conference should be in Microsoft PowerPoint (.ppt or .pptx) format and delivered at the conference on a USB memory stick. Please understand that your PowerPoint Slide presentation will not be accepted to be published in the proceedings; only meaningful text will be published in the proceedings, not slides that need description for understanding. Paper: Size should be 81?2 x 11-inches. Margins: Top and sides should be 0.75 inches; bottom must be 1 inch. Font: You may choose your font, however, try and use standard fonts. The font should be clean and easy to read 12 pt. Layout: Either a one or two-column format. Page numbers: Do not include page numbers. Headers/Footers: Do not include Headers and/or Footers. Drawings: Drawings should be embedded in the files. Place them where you’d like them to appear. Photos: Color or black-and-white digital images if utilized should be embedded in text files. Place them where you’d like them to appear. Printing: We print what we receive. We do not copy edit (but will correct something if we notice it – or if you notice it and let us know). We try to make all papers somewhat uniform, but we do not rework each article. Page numbers are added as we prepare the files for our printer. The deadline for the submission of papers and presentations is February 15, 2025. Please indicate when you submit your paper or presentation if you plan to attend the conference and present your paper in person or if you are submitting solely for publication. Papers and presentations are being handled by Mike Stipick, KC4RI, and should be sent to: KCRI@.... Mike may be contacted at the same email address if you have any questions.

I've looked online, and can find very little information on using an microSD card with this device. Can anyone who actually owns an H4 device let me know of any information they gathered (any links appreciated). They main thing I would like to do is save screenshots when out portable. Thanks

Hello I am looking to use my H4 to generate a signal on HF at -73db and -70db to do some calibrations after a firmware update on a my receiver. Some Nanovna have a tab called "Signal Generator" but the H4 does not (or I can't find one). I Can generate a signal on the frequency wanted by setting the start and stop to the same frequency and can hear the signal on the receiver but is it possible to somehow control the output precisely? It is possible to use the Power setting but they are preset and the only options are "Auto, 2mA, 4mA, 6mA,8mA" and not what I want. Thanks for any help 73 M0KCB

Hello David, The 40M leg is too long. The SWR and RL are rising with the increase in frequency. The 80M leg is too short. The SWR and RL are improving with the increase in frequency. HTH...Bob VK2ZRE