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When I trim an antenna I first measure the resonant frequency.? Then compute the ratio of that to the desired frequency.? Convert that to wavelength, divide by 4 (each side of a dipole is 1/4 wave)

Some antenna materials don't fold, bend, or mutilate. Could cut long, measure the resonant frequency, then reduce in length by a ratio proportional to FreqResonant/FreqTarget. Jerry, KE7ER

Wire diameter, insulation proximity to other object including wood will all make a dipole shorter at lowest SWR. Or otherwise said will load the dipole and make it electrically longer than is is.

On 8/23/20 3:07 PM, davidb1stein@... wrote: <snip> As you get closer to your center frequency, start cutting a shorter amount of wire off the end. Instead of 2-4 inches, now only cut 1 to 1/2

Bob, I think you have misinterpreted the question, but it was stated somewhat awkwardly. He refers to 5 meters of wire for the dipole elements and later calls them cable. Beginners mistake in

Post cited "Hopefully, the resonant point will be higher than the center frequency you want for the dipole". The extra Dipole length (to allow trimming for better Resonance/lower SWR) results in a

DiSlord, Would it be easy to add an SPI flash chip like this to the board... https://www.adafruit.com/product/1564? this one is discontinued but if there is an alternative chip, it would allow for

Folks, Please use the SEARCH feature of the forum.? There is a thread called: voltage sensing diode Look for it?/g/nanovna-users/message/5526 It's D2 beside the battery connector On

frequency, it may not be much of a change, maybe a few MHz. I'm sure you mean a few KHz. Should be clear from context, but just in case somebody is confused...

Hi Steve; Gee... I can attach pix with any of my 3 iPads, 2 iPhones, and my iPod. My gripe is that I can’t use them for much more than lethargic web browsing once Apple obsoletes their support. :-(

You said that you are attached to the "facade of my balcony". Your antenna will be affected by the building structure and the fact that you are close to the ground. Both of these will affect the

Not a stupid question.. Lower than expected isn't unusual - all manner of things around the antenna "loading it down" will tend to reduce the resonant frequency. What I do is fold or crumple the

Thanks Steve! Bob

Are you using bare copper wire or wire with an insulating cover copper wire like house wiring? Generally when I build an antenna, I start with the following formula taken from the ARRL Handbook:

You don't change the SWR by changing the length of the cable.? It's the dipole itself that needs adjustment. Your goal is to adjust the dipole length for minimum reactance at the operating

First you must include the velocity factor of the wire - typically .95.? That brings the length down to 4.75.? Also, as the wire gets closer to the ground, the ground capacity makes the wire look

Hey, I've got a halfwavelengh dipole hanging on the facade of my balcony, it's two 5 meters wires connected through a 1:1 balun to work in the 20m band. I tried to optimise the length by cutting wire

Hey, I've just received my nanovna this week, and started to optimise the length of my half wavelength dipole wire, it's just two 5 meters wires connected with a 1:1 balun and attached to the facade

Here is the latest 'official' firmware update for the H4, it comes from Hugen's own repository. https://github.com/hugen79/NanoVNA-H/releases

wrote: 3 GHz full 2-port would be great if it had 4 receivers, which would allow unknown thru calibration. That’s a massive advantage. But without a display I would personally not buy. Dave. -- Dr.