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How you define efficiency? If there’s no loss, then an infinitely small antenna (a hertzian dipole, for instance) just has 1.5 dB gain over an isotropic antenna. Small antennas have low radiation

Exactly which flavor nanovna do you have? What prompted the need for DFU mode? Secondary to physical damage like deceleration trauma or charging damage?? The more info the better. Jason Burchell

It's also pretty easy to set up a battery powered access point that everyone can connect to. In a Field Day scenario, this is handy for logging, and backups and such, because you can hang a backup

The Samsung S4 connected right up with the H with the TCPUART app. When it came to the server portion I had also checked the box to use the connection by default. On my Lenovo ideapad running Win 10

QUOTE (Jim Lux): .....short antennas have a different pattern than full size antenna, but their "efficiency" isn't intrinsically different). Jim, if we address small tuned loops on transmit, the

The TCPUART app enables a simple TCP connection to the IP network, so it should work with any method of getting your phone and the computer on a network with the same IP address space, ad-hoc or

This is using resonance as a choke, not resonance of the entire antenna. You want your choke to be high Z, so that currents don't flow on the outside of the coax. As far as the antenna goes, if you

/g/nanovna-users/message/33097 Roger

Yes, if it has the ability to be a hotspot that would work. An advantage of "connecting both to a network hot spot" as opposed to making the phone a hotspot/AP is that your computer can then hit other

Jim, I agree. I use the terms access point and hot spot interchangeably. Android or at least the old 5.0.1 version I'm looking at on these ancient Samsung S4's have the ability to turn the phone into

But then ARRL Antenna book says resonance has no affect on antenna performance. Hams like to operate antennas at or near resonance as that’s where drive point impedance is at its lowest value so

It would be a “IP network connection”, so both ends need to be “on the network”, whether by WiFi or wired. If you could set up one end as an “access point” and the other could connect to

Stan, I pulled out an assortment of cell phones last night. Three were Samsung Galaxy S4's, an LTE A910. The S4's should work even though Android 5, the TCPUART program says its good back to 3.5. You

This was discussed 4 years ago and the developer(s) decided not to implement it since you also have the touch screen and at the time, code storage on the original devices was at a premium. A few

Hi Bob, It is now at 295 and working good. Default it was slightly (100Hz) above 300MHz.

I hope you can make it work as easily as I did. My cable was a bit flaky, so the first few times I tries to connect to the vna, it said it couldn't connect, unknown device. But then I plugged the

I cant get the DFU driver to work. WIN11 opsys. I tried all the procedures in the "absolute beginner guide" but no dice. Any suggestions? -- John Mazzone AMVETS Post 826, Life Member. American Legion

Parallel resonance yields the most isolation between the antenna and the coax feedline. SHUNT PARALLEL RESONANCE = HIGH-Z OPEN SHUNT SERIES RESONANCE = LOW-Z SHORT Use your NANOVNA to prove that. Dave

Stan Dye, Thank you so much for that feed back. It helps. I have a few older cell's here to play with. Andy

It's not always small, Dave. The first plot shows VNA R & X for data from a ground probe using a two-port series measurement. The second plot shows the resulting ground permittivity and conductivity.