eHam
eHam Forums => Misc => Topic started by: HAMHOCK75 on March 09, 2023, 02:27:57 PM
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I had an original nanoVNA received as a gift in 2019. It was limited to 101 data points horizontally on its screen. For a spectrum analysis, I have an HP8593E covering 9 kHz-22 GHz. This TinySA Ultra came in a few days ago. I had upgraded to the LiteVNA last year with 1024 data points horizontally.
Now a 6.3 GHz VNA and 5.8 GHz SA can fit in pants pockets. Unlike the original TinySA with a 30 kHz minimum resolution bandwidth, the Ultra has a 200 Hz resolution bandwidth. With its earphone jack on the bottom, it can demodulate AM and FM ( using slope detection ).
(https://www.mediationdangers.com/stuff/wp-content/uploads/2017/07/IMG_3373A.jpg)
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Amazing technology available these days. Wasn't so long ago when such measurement capabilities were only seen in commercial & military service due to cost & complexity, and not affordable to the average small/home laboratory. But not anymore :).
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Who did you end up buying it from?
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I got the nano vna f series, its a few years old but I was able to update the firmware sucessfully. I bought from the
original designer, deepelec. I would like to know the source of your 6.3 gigahertz unit, mine with the update last night
goes to 1 gig.
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Both the TinySA Ultra and LiteVNA which goes to 6.3 GHz are carried by R&L and Zennko. R&L currently has stock on the Ultra but out of stock on the LiteVNA. Zeenko has stock on both. If you like Deepelec, they stock the LiteVNA also.
Both can capture the screen to a microSD card which saves a lot of time if you like to document your work. The Ultra came with a 32 GB microSD card, the LiteVNA did not come with the card. Also, the Ultra allows saving the test set up and recovering the image to it's own screen. The LiteVNA cannot do that. LiteVNA images are viewed by removing the microSD card and viewing its contents on a computer.
Wasn't so long ago when such measurement capabilities were only seen in commercial & military service due to cost & complexity, and not affordable to the average small/home laboratory. But not anymore :).
So true. We older folks are also grateful for the size and weight reduction! My HP8593E portable SA weighs in at 36 lbs.
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So true. We older folks are also grateful for the size and weight reduction! My HP8593E portable SA weighs in at 36 lbs.
We had two sayings in our lab:
a) HP stood for Hernia Producing
b) HP sold test equipment by the pound.
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So now with 200 Hz resolution BW, the TinySA Ultra might be capable of giving reasonable measurement of transmitter IMD in a two-tone test (with suitable attenuators and a dummy load of course)?
I wonder if anyone has tried that yet, to see how well it achieves usable accuracy.
I'm not interested in going to multi GHz, just want to keep my HF transmitter clean.
73, Ed
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Ed,
The answer is that the Ultra is useful for typical SSB 2-tone testing, but only just. The image below shows some promotional material taken at maximum (500 Hz) resolution and 1 kHz per division on the horizontal axis. The 2 tones, separated by about the usual and recommended spacing, are distinguishable and while a full test involving lower-level, higher-order, products would be possible, it's starting to stretch the imagination.
I'm a fan (and owner) of a number of items of low-cost test gear and they've more than paid for themselves in terms of project applications. However, it's also important to appreciate that the demands on test gear are also increasing: serious de-bugging of noise in e.g. digital mode transmitting systems demands 1 Hz or better RBW and simultaneous fast readout, while for many other modern radio applications a ~10 kHz phase noise of -100 dBc/Hz is barely adequate. Rigols, Siglents, etc. will get you to that level but dump you into a world of poor firmware and accessory software curation which, interestingly, can be worse in terms of bug fixes etc. than either the low-end open-source ("semi-random") or high-end (Keysight, R&S, ...) environments.
None of the above is meant to minimize the usefulness of the low-cost gear but, as always, serious application demands a good knowledge of the test equipment and its limitations - whatever your budget.
73, Peter.
(https://i.postimg.cc/8zB5Cqtx/ultra-two-tone.jpg)