开云体育

How to overcome the need to turn off/on every time we plug the USB cable to PC?

Use QRP firmware:

Based on my own trivial experiments, metal enclosure for worse unshielded clone
makes things somewhat worse above 600MHz.
Otherwise, limitations appear to be from internal crosstalk and e.g. mixers' nonlinearity.

On Sun, Nov 10, 2019 at 08:33 AM, KV5R wrote:

I will also note that your vbat offset works well for the 1N4148 diode I
installed; it indicates full for most of the cycle, then 2/3, 1/3, and when it
turns red there are only a few minutes before it shuts down. So it does what
it should! :)

if you worrying about battery indicator, you can try NanoVNA-Q:


it has allows to calibrate battery offset. So, you can tune it for your diode. In addition it shows real usage time battery percent, so if it shows 50%, it means that battery will be discharged after 1 hour (for 450 mAh which has 2 hours discharge time).

Hello Team,

Did anyone sucessfully inserted the nanovna inside a metal enclosure? Will that improve any accuracy and/or stability?

How to overcome the need to turn off/on every time we plug the USB cable to PC?

May I see some examples?

Cheers and thanks in advance!

Luis, CT2FZI

On Sun, Nov 10, 2019 at 06:47 PM, Andy wrote:

I'm not exactly seeing overwhelming evidence that I should upgrade to a
1500Mhz firmware.
I'd probably be better off with an old GDO and a field strength meter up there
;-)

As Rune mentioned above, 1500 MHz is not the main goal for newer firmware. The main goal is to fix errors, bugs, make more stable and more precise measurements, add new features (such as TDR and Group Delay track, which is missing from old firmware).

For example, old firmware have terrible spikes at 300, 600 and 900 MHz, also it returns unstable measurements and errors, sometimes it freezes and don't respond, it don't allows to enter exact frequency and may show wrong frequency (not these which is actually used).

In addition, old firmware don't allows to check Crystal filters, because it has limitation for minimum frequency span.

If you are ok with firmware which has a lot of bugs and errors and don't needs to measure filters, don't needs TDR and Group Delay track, you can stay with old firmware :)

Regarding to 1500 MHz range, new firmware is just allows to use it, but you can setup 50 kHz - 900 MHz range and it will works the same as old firmware. With exception, that a new firmware will have less bugs and errors. The new firmware just allows to use extended range, but if you don't want to use it, you can just don't use it. Just setup 50k - 900 M and it will works the same as old firmware.

For example NanoVNA-Q:
allows to use frequencies from 10 kHz. It works well from 10 kHz. For example, I tested ultrasonic transducers which working on 24 kHz. You can see in attachment. And as you can see I can check resonant frequency (24100 Hz) and even sound wave propagation delay between TX and RX ultrasonic transducers. Note, this is frequency range 20 kHz - 30 kHz :)

It will be just impossible with old firmware

I would pay a double price to have bigger screen, appropriate internal
storage, and wireless capabilities.
Maybe somebody can set up a vote :-)

73 Ady
===========================

I've already paid double to get the nanoVNA-F. With the larger screen, and in a proper metal enclosure, it's a much more useful instrument than the toy smaller variant.

I would be happy to buy a wide-range instrument, but not without a larger screen and a boxed enclosure. I guess that the V2 will be more expensive anyway, so the difference for large screen and boxed should be less.

Cheers,
David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

To put some facts in this discussion I measured the S11 of a a 25 ohm resistor from 0.5MHz to 1500MHz.
The nanoVNA was connected via USB to a PC but running from a clean 5 Volt supply and TX power is fixed at 2
The light blue line in the first picture starts at 25 ohm at 0.5MHz and stays at aprox 25 ohm till around 1100MHz
Also the phase is stable so nanoVNA is usable for S11 till at least 1100MHz.
Although the calibration till 1500MHz looks good (see second picture for S11 if a open just after calibration) real measurements no longer have a lot of relevance, most probably due to some non-linearity in the mixers above 1100MHz
--
Erik, PD0EK

On Sun, Nov 10, 2019 at 02:49 PM, Andy wrote:

OK, so I see quite a lot of firmware updates appear to include 1500Mhz now.

Is it really usable ?

73 de Andy

There are many versions of nanoVNA on the market. My black nanoVNA is fine up to 900 MHz. At frequencies above 1 GHz the track is dirty, uneven, unusable compared to other instruments.
Lucio, I0LYL

I would pay a double price to have bigger screen, appropriate internal
storage, and wireless capabilities.
Maybe somebody can set up a vote :-)

73 Ady

On Mon, Nov 11, 2019 at 8:07 AM Gabriel Tenma White <
OwOwOwOwO123@...> wrote:

The reality is the bigger screen variants don't sell, as people always
seem to go for lowest price. However I do expect other players (probably
flyoob or hugen) to fill in the niche at some point, as no one has a
monopoly on V2 and I expect to see more different designs (unlike V1 which
is all based on the edy555 design).

On Mon, Nov 11, 2019 at 08:34 AM, Ron Johnson-K7UV wrote:

Just curious...what IS the approximate transmit level of the Nano VNA?

65 mVrms for 50 Ohm load (-10 dBm)
182 mVpp for 50 Ohm load
324 mVpp for 1 MOhm load

About -9 to -13 dBm

Just curious...what IS the approximate transmit level of the Nano VNA? Thanks, K7UV 73

They are the same, the difference between V3.1 and V3.0 only increases C38, V3.3 increases R41, R42.
hugen

Re: open source.
V2 design files *will* be open source, both schematics and layout designs (gEDA PCB), and a few simulation files as well (RFSim99 & LTSpice & PLL simulations). The firmware is already on GitHub. The hardware designs will be published at product release time. If anyone wants to look at the designs *now*, you can send me a PM or add me on discord (スメグマ#2236), but please keep it to yourself until V2 is available for order as cloners can work faster than we do and rush a half baked design to market earlier than us.

Re: DL9CAT version 0.4.0-2? I have encountered the following problem. CW FREQ once started can not be stopped,you have to shut down the device.

73 Corneliu
On Saturday, November 9, 2019, 06:03:41 PM GMT+2, DL9CAT <groups.io@...> wrote:

> The only little problem I see in reald is it doesn't reverse text colors (fg/bg) to show which trace is selected, as hugen does.

Should be fixed now. Please test.

73 DE DL9CAT

No further differences with 3.0 / 3.1
I already checked it before
/g/nanovna-users/message/2148

Roland,
I think the computer is set for logarithmic scaling, but the
NanoVNA display is set for linear scaling. Values near zero cause
deep downward spikes on a logarithmic display.
--John Gord

On Mon, Nov 11, 2019 at 04:14 AM, <hugen@...> wrote:

For the enthusiasts to provide a schematic is enough, I will soon update my
PCB to NanoVNA-H V3.4

Hi hugen, could you please share schematic for PCB rev V3.1. This is my NanoVNA PCB, but I don't have schematic for it.

The only schematic that I found is V3.0 (thanks to Larry Rothman). I know, the difference probably is not significant, but I want to know what exactly is different.

Next time to reboot PC. If it doesn't helps and you don't hear USB connected device "ding" sound when you connect USB cable in DFU mode, then go to Control Panel => Device Manager, click on computer with rigth mouse button and select context menu "Scan for hardware changes".

In most case it will solve issue.

I have learned that three clone manufacturers have copied four different NanoVNAs, they are reverse engineering of my earlier versions and claim that they are doing improvements, but they don't know what to do to make NanoVNA work better. .Once I publish the PCB files they can be used directly for manufacturing, but they may sell unqualified products, making it difficult for users to identify what the merchant is selling through photos. I also noticed that some irresponsible merchants showed photos of the versions I made on ebay or aliexpress, but the actual sales were bad clones, I didn't have the ability to stop them, but I could make my PCB better to distinguish. Some regular users may not understand NanoVNA as well as active users in this group, and they will leave a bad impression when they receive a bad clone. For the enthusiasts to provide a schematic is enough, I will soon update my PCB to NanoVNA-H V3.4, the UART port will be connected to the 2.54mm pins, Geeks can make their ideas through the UART interface . I am actively communicating with edy555 and we will bring some group ideas to NanoVNA.
Looking at the images shared by the group users, the version sold by Nooelec should be the version I sold in September. I don't know where they bought the version and sold it, but it was made by me.

hugen

I read that nanoVNA-V2 feels stuck in a price box, so they
won't be upgrading the display size.

I don't get that at all.

Why not offer various versions, e.g. V2a, V2b, V2c with different
display sizes, and perhaps -4, 8, 16 (or whatever) for onboard
memory or some other significant option?

David KD4E