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Dave, Whether you like it or not, both current and voltage are facts of life, and are present and involved in these phenomena. Current is electrical, not magnetic. When you write "magnetic

Look up "pi attenuator".. for 10dB, 50 ohms, the shunt resistor is 96.25 and the series resistor is 71.15 - normally you pick something "close enough". for 15 dB, shunt 71.6, series 136 for 20 dB,

I hope one of our members can help me... I need the values of the resistors on these boards to ensure it stays 50ohms

That entirely depends upon the VNA and what version firmware running on the VNA. The Latest firmware for the Nano_VNA-F can give the following levels that are adjusted via menu selection. Main Menu

I have measured the output of the NanoVNA at around +3dBm. Is there a way to adjust this output internally? Sure I can add 20dB attenuation (and I do), but it would be nice to be able to say I want an

1) The operation of any CMC, current balun, true balun, or..... does not depend on voltage. It's all about current. Voltage alone does not, I repeat, not induce magnetic current in the ferrite

First, thanks for kicking off a terrific discussion, I've learned a lot! Then, a couple of questions… can say more about your actual antenna-feeder-CMC configuration? Have you tried placing a CMC

That's exactly what the problem was, Com5 used by another program. Thanks for advice. Steve -- 73 de Steve GM4

Jeff, I mean, voltage applied to those 12 turns. Short the input pair to make one connection, short the output pair to make the other connection, apply the voltage between those two points. In a

Greetings, The process sounds pretty good to me but I have not used it. Before my VNA I used an MFJ Antenna analyzer to create 1/4 wave lengths of coax. I found an article that described the

Thanks Alan! Yeah the thought occurred to me that a quarter wavelength of any transmission line should behave the same... I was just unsure whether I had to somehow account for the characteristic

Thanks for the info! 73 Joe

If you see this Com5 in Device Manager, it normally means some other device already opened that port.

Hi Using Win10 PC with Nanovna saver Ver3.8 (64K) I cannot connect with my new Nanovna H4. In saver it shows 'Com Port 5 (NanoVNA)' but when I click connect nothing happens. I get the error message

Great. Thank you very much. Most helpful Jorge

Yes, it is a valid method. For non 50 ohm coax, use the same process. Still calibrate with 50. The quarter wave impedance transformation will occur regardless of the transmission line impedance.

I'm experimenting with measuring the electrical length of a piece of coax. To understand the process, I experimented with some RG-58 I had lying around. I made a short adapter to connect a length of

OK guys and gals, attached is my final contribution (try me.....) to the CMC choke evaluation. The bottom line I believe is that there is no single choke that addresses everything. Coax is much

Here are some plots of a 30 MHz. low pass filter for use up to 150 watts. They were very common in the old days before transmitters had adequate output filtering. The filter actually goes down to

This works well with coaxial feeds, but using open wire feeders, I also take the luxury of forcing a balance between the two conductors of the open wire feeders. I used to use such a choke wound with