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Hugen had previously posted the part number in the forum. I think if you search his posts and "LCD" from Nov 2019 through to around Feb 2020, you'll find the post.

That could well be the case, when Sandpiper were manufacturing those antennas back in the day, their test equipment was fairly limited. I believe they are better equipped now. -- Regards, Martin -

Jos: I apologize for not looking at your name... I fat fingered my keyboard....again! [email protected]> wrote:

Joe: Because the LCD is adhered to the board, you will need to pry it loose from its adhesive bond. There is normally a numbering system imprinted on the display, which denotes manufacturer name,

Hi all, I have to replace the LCD screen of my NanoVNA-H4, please what is the type number and/or where to buy ? Thanks in advance, Jos

The impedance of a helical antenna is about 140 ohms. To match that to 50 ohms, you can use a quarter wave of transmission line of sqrt(50 * 140) = 84 Ohms. The bending of the conductor near the

[email protected]> wrote: The usual technique would be to calibrate to have the nanoVNA in the shack, but perform the calibration on the end of the coax. Then when you connect the antenna to the

Dear Aleatrii, Regarding the group, I was not making a whinge at you, just a general frustration that there are three different groups here covering nanovnas and I try to follow all three. I certainly

WONRP, The current charts are on a new factory ended 100ft length of RG8X now. I also think they must be something wrong with the balun as well since there is not much that could be wrong with the

Hi Gunter, I made the measurements in the shack, the antenna was connected to the VNA via 28 meters of RG-213 Coaxial cable. As you suggested I’ll try to make direct measurement directly at the

Nearly everything we know and use is based on science from the past few centuries. It's easy to think that everything we create and use today has been discovered//designed in the past 20 or so years,

I don't know who you are as you have not identified yourself. But yes but the author did not explain himself. 1.??? Take ONE end of the _electrically half wave-length of 75 ohm coax_ (RG-79 type)

Don't overlook the simple stuff. Disconnect the coax from the antenna and use an ohmmeter to check for shorted coax, especially if you are not really confident in your quality of connector assembly.

really both. Sure, there's been innumerable variants of helical antennas developed over the years, and there's papers describing them, but the basics are pretty what Kraus figured out in the 40s.

Yes, indeed, Mr. J. D. Krauss is the master of the helix! Dave - W?LEV wrote:

Interesting that a book written in 1950 is the authority on the helical antenna. From the stand point of theory or practical application? Roy WA0YMH

True. It's a pretty bad antenna even at HF! When that much loss is shown even in the first plot and progressively measures more and more as you step upward in frequency, the loss is all there is.

WiMax? there's a bunch of antennas made for 3.5 GHz >

The general design concept is that the circumference of the helix is approximately a wavelength, and the "pitch angle" is around 12-14 degrees. and the spacing of the helix turns is around 1/4 the

The "natural" impedance of a multiturn helix is about 100 ohms. One either does some sort of matching transformer, or, you adjust the spacing of the turn closest to the ground plane to essentially