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Getting - and using - a NanoVNA really starts a learning curve! And - there's SO much to learn . . . . . -- Doug, K8RFT

Yes the center conductor...

Good evening All. Dick K9IVB, is there any chance that you could email me a copy of that article? Fred - N4CLA If you want to send it direct, it is n40cla@.... [email protected]> wrote:

Wow, I didn’t realize that! Thanks...

I mentioned in another post that the transmission line acts as an impedance transformer. What you see at the end of your 300 ohm twin line will depend on the following factors: antenna feedpoint

I am not an ARRL member so I don't have access to the article. Roger

If you are interested in a board, at $3.00 ppd CONUS, please reply off line [click the “Private” button]. The first order is sold out and there is sufficient additional interest for a second

Well, sometimes you can't get to the antenna (or your being close to it perturbs its behavior) There are two approaches to this: 1) calibrate the VNA with the feedline inside the calibration plane

Hi Andrew, ? ? The 468/f formula is based on (a) a perfect conductor and (b) a dipole antenna in free space.? In the real world, antenna systems are affected by the environment, such as a height

Hooray! No... now you have divided the problem. Divide and conquer. NOW read all of those prior emails and begin to get your head wrapped around the issue of HOW DO I GET MY ANTENNA CONNECTED TO MY

Just measured dipole directly without twin-lead; right on expectations! Reactance was 0 at 9, 18.3, 27.8, 37.8, 47.3, 58.5, 67, 77.6, and 86 MHz. Alternate ones, when X moved from capacitive to

Andy, What you have constructed is commonly known as a "doublet" antenna (a dipole fed with balanced feedline). The most famous version is the G5RV. If you search with Google on "doublet antenna" you

You have the antenna in the attic so I assume you can reach its center point. Maybe not. But if you can, just clip your vna to the feed point and take a measure. I had a 66 foot NVIS 40 meter antenna

You are feeding a balanced antenna with a balanced line. No balun is required at the antenna. However, at your transmitter (or NanoVNA) you have an unbalanced input (unless you are using a tuner with

Without a proper balun (not a transformer !!) or common mode choke, the NANO and anything it is sitting on or your hand or arm will become part of the measurement. When you make impedance measurements

On 9/22/21 7:16 AM, Andrew Kurtz via groups.io wrote: > I have a dipole antenna in my attic, made of bare 14 gauge copper wire. It is 49.916 feet long, and the feed point is within 1.5 inches of the

D.? The 468 rule of thumb is not that accurate. That is just a good starting point.? ?It does not allow for the diameter of the conductor or any nearby objects.? The difference between bare Copper

I have a dipole antenna in my attic, made of bare 14 gauge copper wire. It is 49.916 feet long, and the feed point is within 1.5 inches of the center. Thus, the “rule” that f=468/L suggests the

$23.99 ???? for a tool that usually costs a few bucks in any network equipment store, not to mention the usual Chinese vendors on Ali and Ebay.

I bought these for RG213 and RG58 - Don’t waste your money Still using a carpet knife and side cutter!