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So you'd make a Rseries L series, C shunt, low pass configuration? I think that won't have the effect you expect. Don't forget that those inductors have a fair amount of resistance, too. In any case,

Jim, Then Miro's question remains: What happens to power reflected back from the antenna feedpoint if there is no antenna tuner? Without a tuner, it is not all getting sent back out to the antenna.

Only if the transmitter has some sort of isolator (in a logical sense) to push the reflected power to a load, and that's pretty rare in a HF transmitter. What really happens is that the transmitter is

I use a small zippered cases for my VNA that was made for a small PC projector. I has a carrying handle, rings to attach a shoulder strap (that I don’t use) and plenty of room for a clear box with

Not necessarily - for small mismatches, the tuner, even at the end of a transmission line with 10% loss (1/2 dB) makes it so you don't have to go out and keep readjusting an antenna that's narrow

Hello! Would you recommend an LC-circuit as an IF filter? I'm looking into using one of [url=https://static.chipdip.ru/lib/261/DOC005261729.pdf]these[/url] SMD inductors (~hundreds of μH) as a coil.

@Dr. David Kirkby: Just like Dragan Milivojevic, I am also curious to hear what the flaws are in Larry Benko's videos. I actually find his videos very interesting and helpful. But I also understand

Folks, You can translate/convert PDF documents online at: https://www.onlinedoctranslator.com I translated the document to English and attached it. Enjoy! Larry

Here is an application report on the NanoVNA-H and SPICE simulation. The report is in German. Enjoy!

If you want some encouragement read Kurt N. Sterba’s articles from the Olde World Radio journal. It’s free now. That’s $0.00

Antenna tuners cause any energy reflected from the antenna to turn around and head back out to the antenna again. So if the antenna is reflecting 1/4 of the energy back to the antenna tuner, after 2.5

Jerry wrote: "...No, you can't just add transmission line length and get any purely resistive load looking into the transmission line that you might wish." I agree, having complex impedance involved

...I hit "reply" too soon... ... given: * short run of low loss t-line * no match between TX, t-line, antenna impedances * antenna tuner makes t-line/antenna appear to TX as TX's impedance (SWR at

So, based on what Dave and Jerry are pointing out, I have two VALID conclusions 1) Antenna tuners suck! They make t-line/antenna go gently on TX, but they hide what's behind them. Strive to have (at

after careful calibration the swr seems to be reading correctly with high values on the edges [email protected]> wrote:

If you have at least a half wavelength of open wire ladder line, then the VSWR is equal to the maximum RF voltage you can measure across the ladder line divided the minimum RF voltage you can measure.

To properly assess the SWR along any transmission line, one must measure BOTH current AND voltage at the same position along the line!! A voltage-only or a current-only measurement will indicate

It does get confusing when neither end is properly terminated to the characteristic impedance of the transmission line. You have reflections from both ends, and reflections of those reflection, until

I had that problem too. I initially gave up but tried a day or two later ( maybe a different Aliexpress trader and got my town on the dropdown. I am waiting for imminent arrival. As far as working at

Also you might want to check Harbor Freight. They have some really nice Pelican case clones and a small one that works quite well to hold the VNA and accessories. They are quite rugged for field work