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Re: .NanoVNA-H v3.5_L: white screen - how do I connect USB to fix?
Hello, In the files section you will find a process to recover from "White Screen Recovery". Follow it PRECISELY STEP by STEP!. If that does not work you could try, for the lack of a better term, a
By Clyde Lambert · #39766 ·
Re: Am I in the right track ?
The image that shows a SWR of 2.6 : 1 (the sixth image), all you need to do is add an inductor in series to cancel the -j 45.6 ohms. At 916 MHz that would be 7.9 nH. In reality, 1.86 : 1 is not bad
By W0LEV · #39765 ·
Re: Building Pi Network with VNA given values
You can actually calculate the values of an L-Network's two components without knowing Q. It is sufficient to know just the value of the load impedance and the impedance you want to transform that
By Jeff Anderson · #39764 ·
Re: Am I in the right track ?
Roger, Thanks for this advice. I'll try it out tonight. Look at the picture and zoom it (not zoomed it does not show up properly), you'll see a blurred larger line around the feedline. This is the
By Nico · #39763 ·
Re: Building Pi Network with VNA given values
L-network values with the nano and then with the AT-100M Pro automatic antenna tuner: I measured one dipole antenna of mine (antenna fed with 1:1 balun, and 72-ohm Belden 8222 twin lead) with a
By Orrin Winton · #39762 ·
Re: Building Pi Network with VNA given values
I'm missing a lot of information to understand (in French) your participation. I remember the last line: A 3-piece Pi adapter can be upgraded to a 2-piece L adapter. If impedance matching is the
By Fran?ois · #39761 ·
Re: Building Pi Network with VNA given values
All four are all 2 element ell networks. If the values have been calculated correctly each one would provide the required match. (1) has low-pass characteristics. (4) is a high-pass network. The
By David McQuate · #39760 ·
Building Pi Network with VNA given values
Hi All. I need to build a Pi Network for my circuit as shown in the fig below. 1741926237187.png So I have a 'Pi Matching Network' in my circuit. The datasheet asked me to build a Pi Matching
By shlomo537678@... · #39759 ·
Re: Am I in the right track ?
Do you have a trace inside the board to be the other half of the transmission line? One turn through the ferrite is not enough. The impedance goes up approximately as the square of the turns.
By Roger Need · #39758 ·
Re: Am I in the right track ?
Hi everyone, No, I haven't abandoned yet ! I got my revised pcb (attached picture) yesterday 1- Revised ground plane dimensions which I made the same as the test board shown in the antenna
By Nico · #39757 ·
Re: Help with LPF Measurement
Very good Mitch. Happy to see you suceeded in beating the electrons into submission. Lesson learned... Neatness counts.
By alan victor · #39756 ·
Re: Help with LPF Measurement
yay indeed.. Pretty cool.
By Jim Lux · #39755 ·
Re: Help with LPF Measurement
THAT looks much better built .. and shows the predicted results ... GOTCHA :-) looks neat .. and works like it should so you see its very often not just the components you use but how you arrange
By Siegfried Jackstien · #39754 ·
Re: Help with LPF Measurement
Jim, Dave, et al., Thank you very much for your suggestions. I rebuilt the filter using discarded SMA connectors I found in my junk box along with actual 270 pF caps that I ordered overnight from
By Mitch NK3H · #39753 ·
Re: Help with LPF Measurement
This - get some 4 leg SMA jacks and solder two of the legs to the copper clad at the edge of the board. Cut the upper two legs off. That will give you a nice transition. Depending on where you are,
By Jim Lux · #39752 ·
Readings are not correct for NanoVNA F V2.
Does anyone have a web-site or youtube that goes through the set-up on using the F V2 for checking Coax lengths. The new one I have does not show the correct length, example a known 15.24m / 50ft coax
By CLIFTON HEAD · #39751 ·
Re: Help with LPF Measurement
How do you know it's filtering the harmonics out? Feeding in a square wave (into a non-resistive load) might not have the harmonic structure you expect. It's really hard to interpret the wiggles after
By Jim Lux · #39750 ·
Re: S-Parameter Plotter
Larry, I still use Brian's excellent antenna simulation programs today. In fact, just about every week. (Different story not for here.) But, I run them on both a very new macOS computer and a
By The Greene Family · #39748 ·
.NanoVNA-H v3.5_L: white screen - how do I connect USB to fix?
I couldn't connect to the unit and somehow managed to wipe the processor. I've tried resetting it to reconnect, but the only response I get is in STM32Cube Programmer 'UR is set by HWrst' or something
By Taracait · #39747 ·
Re: Help with LPF Measurement
Things are beginning to look a bit more like a LPF with the "ground" connected! Other suggestions have been made which are right on. Keep us posted on your progress. Dave -
By W0LEV · #39746 ·