Fransesco,
Thanks for the site and reminder.
Dave K8WPE (also a geriatric memory at 77)
David J. Wilcox¡¯s iPad
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On Mar 5, 2022, at 6:26 AM, Francesco <realfran@...> wrote:
? Please read this page: *On the "OLD DAYS" the calibration was necessary like today you needed to balance the bridge (this came from my geriatric memory).*
*Sent:* Saturday, March 05, 2022 at 10:57 AM
*From:* "David Wilcox K8WPE via groups.io" <Djwilcox01@...>
*To:* [email protected]
*Subject:* Re: [nanovna-users] "Zero calibration" (or "no calibration") question
Can someone explain why my YouKits FG 01 and RigExpert A600 (and even my old MJF 269) analyzers don¡¯t need calibration every time I use them compared to the NanoVNA? What is the difference in the operating firmware or actual operation?
In the ¡°old days¡± I never had to calibrate anything when tuning my antennas with my GDO or noise bridge? Ha!
Dave K8WPE
David J. Wilcox¡¯s iPad
On Mar 4, 2022, at 3:19 PM, Miro, N9LR via groups.io <m_kisacanin@...> wrote:
?On Fri, Mar 4, 2022 at 11:02 AM, Jim Lux wrote:
The other plots are antennas measured using the cable calibration and not.
This VERY interesting - difference between measurements with calibrated vs non calibrated varies from just a fraction (1 or 2 db) to sigificant (10db and more).
If I understand correctly, your "calibrated" values are for SOL done at the port, or short length of coaxial cable connected for measurements, right?
My primary interest is HF (up to 30MHz), and (as expected) differences are more under control at the lower ranges.
Would be cool to have a "zero calibration" built in, so I can have a an easy option to get to that "default" state and accept the unknown impact of the unknown length of a t-line from nano to antenna feed point
David Wilcox K8WPE