Beware of cheap underperforming clones

As of 2022 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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Open, Short, Load - Red Cap

Anthony 2022/03/26 03:09

Forgive my ignorance, please, but what it the red cap for that is included with the test bugs.  Thanks!

Siegfried Jackstien 2022/03/26 13:15

dust cyap to protect the ports if not used?!?

Am 26.03.2022 um 11:09 schrieb Anthony:

Chuck Kelsey 2022/03/26 08:19

Way to big for that. I've concluded that there is no real purpose and
that it was put on there to make people ask questions. LOL. If it was to
keep debris out, why no protection on the open and short? See, another


On 3/26/2022 8:15 AM, Siegfried Jackstien wrote:

Brian Morrison 2022/03/26 14:12

On Sat, 26 Mar 2022 03:09:31 -0700
"Anthony" <> wrote:

> Forgive my ignorance, please, but what it the red cap for that is included with the test bugs.  Thanks!

It's to protect the cal standards against dust and grit ingress, really
you should put one on each standard but the load is probably most
susceptible to contamination, the open least and the short can simply
be blown clear of any dust if you don't have a cap.

The cal process is fairly resilient at the frequencies this VNA can
reach, it gets much more difficult when you get to 13GHz or so and
higher because the wavelengths are so much smaller and a mis-seated
connector can produce significant phase errors.


Brian Morrison

"I am not young enough to know everything"
Oscar Wilde

Anthony 2022/03/27 08:18

Thank you for the explanation Brian. This would explain why they only
provide 1 cap and it was on the load.


Anthony (N2KI)

On Sat, Mar 26, 2022 at 10:12 AM Brian Morrison <> wrote:

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