开云体育

If you write the node equations for a parallel LC with an R in series with the L wo= 1/√LC × √1-R^2 × C/L Yes, the series R will perturb the resonance point from the expected value.

Thanks, interesting! How is that computed? But the result however, is the same with Serial Resistance = 0 Ohm in capacitor and in coil; Except I get beats on top of the 888630 Hz waves, probably

I got my crystal from a cheap clock in my junk box that had died from mechanical problems - the crystal worked great! M

root (LC) is only true if R=0 If any R is present either in series with L or C, The root (LC) is modified... downward in freq...

Simulations show Currents do NOT cancel at the Parallel LC-resonance frequency, contrary to what we learn is one of the main characteristics of parallel resonance circuits. Why? Testing various LC

Larry, Thanks for the info on how to use the SD card. I have not used the time command yet as thought I should install the crystal first. Ken, NU4I Sent from my iPod

The 32KHz xtal is only needed if you want a real time of day clock on your unit for accurate dates on data saved to the SD card.? Without the xtal, you'll need to turn on the Nano, set the time using

So does mine but it still was a clone, nothing major, few resistors where there should be none and some wrong component values. Only way to be sure is to buy from Hugen store.

I bought my H4 several weeks ago and it did include the microSD card holder attached to the PCB. However, the case did not have a slot cut in it for access. I'll do that myself if I decide to use it.

So just to clarify - are the new H4 units from R&L Electronics presently shipping with all required hardware to use a (user supplied) microSD card? 1) Or must the above discussed 32KHz crystal first

It was a long time ago but I did try and buy the Hugen version with the blue PCB. I just checked and it does say nanoVNA-H v3.3 on the blue PCB and the case and lettering are the same as the Hugen

AFAIK all open frame versions are clones. I have one that I have updated to the latest version of the schematic, works ok but there were some really weird component values originally. It would not

There are at least two members of this group who are confused about the NanoVNA-H4’s ability to write sp and screenshot files to micro-SD cards and what needs to be done by us to accomplish this

You need the Xtal only when you want to have the date/time displayed correctly. Jos Op 25-3-2021 om 09:43 schreef Rui Valente:

Hello I installed the latest version 1.0.50 and i solder a new SD card slot...them i tested 3 different sd card and different capacities but anything happen in the menu sd card (no error message)

Arie, It took me a little while to figure out what a balloon was. I passed the video and tried googling Ballon choke. But then it hit me. The videos are great. They are long but good.

I fix one problem in DSP code (for H version) in 1.0.50. H4 use DSP instruction and more faster/accurate in calculations DSP code for H: do{ int16_t ref = capture[i+0]; int16_t smp = capture[i+1];

Larry, Sorry. I meant capacity. I have a 32MB microSD card that I will try. Thanks, Mike N2MS

I also tried a very harsh test with the nanoVNA. I put two 820pF PPI 1111 caps in series and compared the ESR to just one 820pF PPI cap. In theory, the ESR should double and the Q curve should be the

I'm fairy sure my nanoVNA is an H as it had H firmware on it when it arrived. It was made in 2019 and is the open frame 2.8" model. At the time I did try and buy from a proven seller to get a well