Yes, is it possible to add input protection into new versions at the factory. ESD101B102ELE6327XTMA1 diodes are available at least now from Digikey, but they are a bit small for manual soldering.
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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Add ESD diodes to new versions?
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