开云体育

Hi Shabaz
UPS, here are the documents
Kind regards
Kurt

-----Oprindelig meddelelse-----
Fra: [email protected] <[email protected]> P? vegne af Shabaz Yousaf
Sendt: 5. marts 2024 16:27
Til: [email protected]
Emne: [N2PK-VNA] SDR-Kits Female SMA Calibration Kit query

Hi,

I've purchased a SDR-Kits Female Calibration Kit of Rosenberger parts, it's intended for DG8SAQ VNWA, but I don't have that, I intend to use it with N2PK VNA, and R&S FPC1500 VNA.

I had a question, which I'll eventually e-mail SDR-Kits with, but I thought it would be worth asking on the N2PK mailer first, since others may have done the same thing as me and obtained this.

The question I have, is (perhaps a really basic one! in which case I apologize), in the screenshot in their datasheet, they show an offset delay, and a derived electrical length. A snippet from the datasheet is shown below; you can see the two-way delay of 84.70ps, and a one-way electrical length of 8.87mm.

Using some simple math, I had previously believed that the offset delay can be converted to electrical length by multiplying by 0.3, i.e. 84.70ps would become 25.41mm, and half of that (since they are using two-way delay for some reason) would be 12.705mm.

[cid:fd356d6e-2451-4e33-b967-7186a635a220]
Link to the PDF full datasheet:

I installed the VNWA software and entered the 84.7ps value myself, and it calculated 8.887 mm mechanical? length, so that settles that the datasheet has an older incorrect screenshot, which is minor but I'll raise it with them since it is confusing to readers. However, more importantly, I'm curious how the VNWA software arrived at that value anyway, because a conversion of 8.887 mm mechanical to electrical would be 1.5 times 8.887 which equals 13.33mm , but it's still quite different from my computation of 12.705mm.


[cid:f102a3a1-f2fd-44a2-a45d-f69c90ba23ba]


My question is, how did they come up with the electrical length? Am I calculating it wrong, or is the VNWA software calculating it wrong? It's important to me, because on my FPC1500 VNA, the only values I can enter are lengths, so I need to know if I should be typing 12.705, or 13.33, or something else! : ) [cid:8801385d-6178-4b9f-8cc4-f688d723556c]
Personally, I believe it should be 12.705, because when I calibrate like that, I believe I'm getting decent measurements. But I'd like to know if this is just luck, or if I am actually using the correct formula.

Any help would be gratefully appreciated.

Many thanks,

Shabaz.