Beware of cheap underperforming clones

As of 2023 there are many badly performing clones on the market. V2/3GHz NanoVNA uses parts like ADF4350 and AD8342 which are costly and clones have been cutting costs by using salvaged or reject parts.

See official store and look for V2 Plus4/V2 Plus4 Pro versions only to avoid getting a bad clone. We have stopped selling V2.2 versions since October 2020, so all V2 hardware that are not Plus or Plus4 are not made by us and we can not guarantee performance.

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"Exception: No error" QT v1.1 connection error #features

YH 2023/05/31 16:30

I am trying to connect by QT v1.1, but following error has occured.

Is there anyone who has same connection error with me?

William Hays 2023/06/16 02:34

Having the same problem.

Installed the the "CypressDriverInstaller_1.exe" USB-CDC driver.

I connect and power on the VNA6000 to the computer. The VNA appears under "Device Manager" as COM13.

When launching version 1.1 of NanoVNA-QT, I cannot connect to the device listed as COM13.

Tried changing Port number with no effect.

VNA6000 has the latest firmware 20220814

Connects OK with VNA-Saver.

Dave (G1OGY) 2023/06/16 23:01

You may have success with the alternative way to specify a COM port
numbered > 9:
Please review this article:
Dave, G1OGY

On Fri, 16 Jun 2023 at 16:14, William Hays <> wrote:

William Hays 2023/06/17 17:02

Thanks Dave,

Still no luck.

William, AE4QL

lance fisher 2023/08/18 07:56

Dave's answer is appropriate if you are able and willing to modify the firmware but for most users the easier option is to go into Device Manager and change the port number to something less than 10.  Open DM, double click the USB port associated with the NanoVna to open the properties window.  Click the "Port Settings" tab and the "Advanced" Button. Then click the pull down arrow for the COM Port Number field and select a new port #.

Windows saves the assigned port# and deviceID for every USB serial device that's ever been connected to your PC and only one deviceID can be associated with each port# so if you've connected 8 or more such devices all the port#s less than 10 will be preassigned (COM1 and COM2 were traditionally assigned to hardware / non USB  ports and won't be automatically assigned to a USB device).  You can re-assign any port# to the NanoVna USB serial connection that's not currently connected physically.  The only downside of this is that the next time you connect the other device that used to be associated with the port# you re-assigned that device will get a new port# assigned and you may need to configure that device's software to use the new port#.  BTW you can assign COM1 or COM2 and since most newer computers lack hardware serial ports those two are usually open.

If you don't know which port# is currently assigned to the NanoVna, disconnect or power off the VNA then reconnect  / power on the VNA with Device Manager open.  The currently assigned com port will disappear and reappear when you do that.  You can also select "Show Hidden Devices" in the DM View Menu to see all the assigned ports for devices not currently attached.  With Show Hidden Devices checked, the devices currently connected are indicated by a darker USB plug icon.

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