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One other thing that might be taken into consideration is calibration of the NanoVNA. Are you testing the antenna, or the antenna system? When I want to test a new home made antenna, I calibrate the

Hi Folks, A few last comments and then I'm moving on. Today I modeled (approximately) Jeffs antenna using 4NEC2 and I made a few assumptions based on Jeffs installation. I built my antenna last night

I agree, I’m very new to all of this and it is a bit overwhelming but it is a great group, especially the pros! -- Sent from Canary (https://canarymail.io)

I have to say that my experience with this group is the best I have ever had. omg! Years of forums with arrogant responses, and mostly no help. Thank you all for letting me learn without the slams.

How good are those SMA to PL259 and SMA to SO239 connectors that are popular with some NanoVNA users? A back to back test was done using a NanoVNA-H4. Results attached.... Roger

Here is another test result. 10 feet (3 meters) of RG316 with SMA connectors on one end an 100 ohm SMA resistor on the other end. SWR was 2 at 1 MHz and then went through peaks and valleys with

Th trace labels are correct. The "SMA barrel" plot was done by attaching a SMA to PL259 adapter to the NanoVNA. Then a SO239 barrel was added and the RG 213 attached to that. At the end was a 50 ohm

Hi Mike, The application was not for use on an HT but rather for an outdoor installation using 3 radials and I wanted to see what the actual feedpoint impedance and SWR looked like as close to the

I like look at the swr in real life conditions. If one is using this as an antenna on a handle talkie shouldn't you simulate this by removing the radials.? Mike N2MS

Hi Gabrielle, The NanoVNA is a great tool for plotting frequency response and impedance characteristics of a filter and therefore no need to use your signal generator. Don

HI to all I own a FY6900 device, a cheap but very complete generator (mine is the model working up to 60mHz). Till now I've used it only with an oscilloscope, but I would like to employ also with a

Hello Roger, I may have missed something here, but it seems to me your trace labels are reversed. The "top - SMA barrel" trace has much larger SWR ripple and a predominant capacitive reactance loop on

Two more pictures using 10 feet of RG58 Coax connected to the vertical. First Picture is with SWR Plot scale set to 0.25 per division and second picture with SWR plot scale set to 1.0 per division.

Here is a picture showing my test vertical mentioned in my above post when I had it connected directly to the NanoVNA-F using just a couple of adapters. Note in this picture the NanoVNA-F was

Hi folks, I somewhat agree with what others have said and Rogers demonstration shows one issue but let me make some additional observations/comments. My comments below ignore some minor effects due to

I suspect some inductance between your metal (?) mount and the feed line running parallel to it. Consider lengthening your feed line by a couple of feet and put a loop in it along the vertical

The ripples you are seeing are not unusual. It is not due to the antenna - it is the transmission line and/or adapters being used. . When the impedance of the transmission line is slightly different

Hi, What you are seeing is perfectly normal and simply represents the fact that the antenna feed impedance (at the antenna feed point) does not exactly match the coax impedance. It's certainly pretty

I'm not sure why the ripple is in there. I have never seen that when I do an SWR measurement. The minimum of 1.2 isn't bad, but the frequency is 406 MHz. What band is the antenna for? Is it a

That antenna is not the best with only 3 "stingers" as a skeleton image plane. It's pretty spartan! The "wiggles" you are seeing at the end of the coax reflect a small SWR on the coaxial line. The