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No, not necessarily. Some types of these do not short both conductors together and even if they do, there's no guarantee that the potential of the feedline will be the same as that of your device

Yeah, longer would be better, and there's no need to cut a specific length to make the measurement. Any reasonable length you have lying around can be used as long as you can measure its physical

Exactly.? Or you can put in 100 for the VF, measure the length, and compare the measured length to the actual physical length.? VF = physical length/VNA length@100 VF I'd use more than a meter long

I have an idea for finding the velocity factor of any cable. Please let me know if this could work. The NanoVNA can measure cable lenth accurately if the cable’s VF is known and can be input into

I would always discharge an antenna coax before measuring, just to be on the safe side. However, I would assume that if one has an unun, balun, or matching transformer between the antenna an receiver

I always connect my coax from all antennas to ground when not in use. No problems with static then and I can measure them any time I need/want to. Well, as long as I've just disconnected them from

This is true, and one of the wires connecting one port to the other might be "inside the VNA" (i.e. the chassis ground)

Megohms. I used to use scrap black vacuum hose - it was UV resistant and happened to be conductive, and best, it was cheap. Now, I'd probably just use a 1 Meg resistor if I had one.

If your antenna is fed with coax, it appears as a single "wire". However, in reality, it consists of two conductors: 1) The single inner conductor, and 2) The outer braid. Fields are conducted to/from

I have a 1 MΩ permanently connected across the output of my transmatch. When the feedline is disconnected from the transmatch (most of the time), I have a 50 Ω resistor paralleled with a 70 volt

Andrew . . . The single port needs two wires to function. https://en.wikibooks.org/wiki/Circuit_Theory/One_Port_Devices It does seem perhaps a little confusing, but the article above shows a port with

Just a quick question. How many ohms would you suggest for that bleeder? Fred - N4CLA [email protected]> wrote:

You are correct in connecting this single series tuned "filter" between the two ports. The coaxial braid is taken care of inside the VNA. Usually, these "filters" would be mounted inside in some sort

Gee, I sent this with a picture that didn’t come through! Picture a home-made coil, 3 turns on 1/2” diameter, with a little capacitor soldered to one end… No coax or coax fittings anywhere...

https://www.youtube.com/watch?v=RAT2v8Eax-o This is a video of what voltages an antenna can present to equipment. Poor video, but worth watching. 73, Joe, K1ike

You folks have been very helpful! You can tell that I am a rank beginner, but I still think we sometimes talk past each other. Here is a 100MHz band-pass filter, simply an inductor and a capacitor in

bleeder across the antenna's lead in the station to drain static accumulation and never mind if it's a "grounded" antenna. A permanent bleeder like that does not affect reception or transmission. For

Hello Syd, When you have read the beginner guide, have a look at: /g/nanovna-users/wiki/16592 73, Rudi DL5FA

I use my wedding ring to short the coax... Or make sure I touch the coax shield and center... You can still get a static discharge from the antenna at the base. 73, and thanks, Dave (NK7Z)

Syd, I suggest you read this document which will get you more familiar with the NanoVNA. It is in the files section of this group