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Try these firmware.

Hi, Rudi!
The length of cable does not matter in this measurement. My cable length was 33cm and it was open.
See DJ7BA message #8655 about this method below.

It is a weird industry where cloners bring the price down but often also
introduce sub-optimal components, leading to bugs and other out of spec
behavior.

Not new:

@Andy
Could you please tell the length of the coax cable, and if the end was open or shorted.
I know of possible length of 30, 50, 70 cm.
73, Rudi DL5FA

Hi DMR,

unfortunately the portrait mode is not working. The Menu is outside the display and not useable.

The programming on the UI seems to be "hardcoded" to the landscape mode.

On Sun, Dec 29, 2019 at 09:48 PM, Gary O'Neil wrote:

Furthermore; the results imply that the only sources of uncertainty that exist
are that which is induced by the inaccuracy of the calibration standards used,
and the repeatability of the measurements.

Gary.
This is true by definition as the VNA measurement system can be fully characterized by the measurement of three independent calibration standards. Even if these standards are not known, comparing measurements from VNA's calibrated using the same 3 standards will lead to the same results within the repeatability of the measurements of the VNA's

--
NanoVNA Wiki: /g/nanovna-users/wiki/home
NanoVNA Files: /g/nanovna-users/files
Erik, PD0EK

The screenshort shows how to make Lambda/8 measurements with the help of NanoVNA-Saver step by step.
DUT- is the cable supplied with NanoVNA.

Hello everyone, we just released firmware 0.0.5, and sorry for coming so late :-)
NanoVNA-F firmware 0.0.5 released ! up to 1.5GHz, bug fix, REAL IMAG R X trace format, the new PCB has arrived.
1. support measurable frequency to 1.5 GHz, default setting 1 GHz, accurate measurement up to 1.35GHz.
2. fix: unexpected 0.3dB offset of s21 in thru
3. fix: mark all off bug
4. fix: clutter display when standing wave ratio is infinite
5. add version & info command
6. add REAL IMAG R X trace format
more detail:

Thanks ! And the next version will be released in January 2020.

@Gyula Thanks, that thread on the 'NanoVNA does not want to start' is probably the best source on the topic.
(direct link: /g/nanovna-users/topic/32846852#3565)

From what I've gathered after reading it:
- Herman's NanoVNA symptoms are exactly the same as mine.
- Replacing the IP5303 with a new IP5303 did not fix his problem.
- Replacing all 10uf (C1 45 46 49) and 22uf (C47) capacitors (as suggested in message #967) did not fix the problem.
- Making use of the KEY function of the IP5303 allowed the chip to reset it's deep sleep mode and power on normally, but (if I interpreted the messages correctly) this introduced the behavior that the device can no longer be powered on when connected to a PC (unless the NanoVNA is already up and running).
- The value of C1 in the NanoVNA schematic (found at ) shows a value of 100nF, not 10uF
- Replacing the IP5303 with a IP5305 fixed Herman's problem.

@Bilbo we may be looking at a different schematic where C1 is probably located elsewhere? Mine has a 100nF value at C1. I checked C1 in-place but did not immediately see a problem. I may end up replacing it with something bigger, but I'm not sure if that's where the real problem lies.

@Bob Fortunately, my units remain on when switched on, but they do not (always) power on. I'm curious, did you replace it with another IP5303 or the IP5305? Any complications in desoldering it?

@Gyula Yes, I understand there are now various clones on the market and it is not always obvious who came with the original idea. It is a weird industry where cloners bring the price down but often also introduce sub-optimal components, leading to bugs and other out of spec behavior. Thanks for the background information and clearing this up.

Considering all of the above I will experiment with the KEY function on pin 5 of the power controller IC (pushbutton with 10k resistor to GND) as this is the simplest and least intrusive hack. As a backup plan I have also ordered the IP5305 chip as a replacement (actually, 10x for $3.40). They are in a SOP-8 package, so not too difficult to solder. The chip has a thermal pad underneath and will probably require a hot-air soldering gun to remove in a non-destructive way. There are some slight differences in how the LEDs are driven, but I think they are compatible in all other aspects.

Hi Erik;

Although it was not entirely clear to me at the time, I believe GIN$PEZ confirmed your statement to be correct.

Viz.

***

From Post #6529:

(5) We did * N O T * invent this relation [#52]:



We just simplified the given one [#16]:



-
as, perhaps, they did that others before us, although we don't know if something
that was really happened.

This is easily verified by anyone who would like to use simple, high-school algebra
on these expressions, by ignoring their complex "nature" and substituting:

(i) g, G in Hellenic gamma, Gamma

(ii) -1, 0, 1 in A, B, C, and

(iii) s, l, o in a, b, c,

respectively, and proceeding with the resulting eliminations.

***

I believe this was also confirmed by their proof in Post #8013

Viz.

***

We just uploaded a substantially updated improved proof at:



***

However; in this new thread, confirmation of the equivalence of the two equations doesn't appear to be relevant to the confusion that still may exist from my earlier understanding of this.

I have to catch up on my study of the original thread leading up to this, but I anticipate that the proof offered in Post # 8653, represents a reformulation of the same model to achieve the 2 - port equations. Be forewarned however; that this is but a guess on my part.

This new thread appears to move the focus away from the core equations (which I believe remain unchanged other than perhaps being simplified in their execution), toward a focus on the topic of most relevance to their originally stated goal... that of fairly and optimally quantifying and comparing the measurement results obtained by two independent VNA's. That is at least my interpretation of their mission.

Their use of the ratio of ratios test is a new revelation in their research that enables the measurement of a distance between two identical points made on independent but linear scales and evaluate them for equivalence. In applying this test to measurements made on their NanoVNA with those made on their HP-8505 VNA using exactly the same loads for those measurements, they have been able to demonstrate that the data results correlate almost exactly.

It should be clear to the casual observer that the NanoVNA and HP-8505 VNA measurement platforms are physically quite different. It should be equally clear that the high correlation demonstrated could not be realized if the measurement uncertainties were not mitigated. This observation becomes even more profound in light of having placed no value or tolerance restrictions on the loads used to perform the comparison tests. I believe their results reveal and confirm with great clarity Hackborn's** assertion that "The Automatic Network Analyzer system simply leaves the errors in the system but measures and remembers them." Furthermore; the results imply that the only sources of uncertainty that exist
are that which is induced by the inaccuracy of the calibration standards used, and the repeatability of the measurements.

--
73

Gary, N3GO

** The Microwave Journal, May 1968 (pgs. 45 - 52); "An Automatic Network Analyzer System" Richard A. Hackborn, Hewlett-Packard Co., Palo Alto, California

TDR = Time Domain Reflectometry.? You send a pulse down the line and observed the reflection.? A matched line won't reflect anything.? Any other condition and you will see a reflection.
The nanoVNA has, for me, made TDR obsolete.? I can measure SWR, line length, antenna impedance, and virtually any other parameter related to the ordinary use of antennas and transmission lines.
So I put away my TDR pulser and, while I was at it, my return loss bridge.

On Sun, Dec 29, 2019 at 06:31 PM, Birdman wrote:

The vna you showed via the picture you uploaded is different from the unit in the ebay listing you linked? The ebay add shows and older type unit with no case, and mentions it will come with a 350ah or 500ah battery.

Is that the correct link you ordered/received the new unit from? Thanks for your help....
============================================================================

Chris,
I think you confused my post with one of the other members. My links have been to hugen's Alibaba store, . That is the only place that I currently know you can be sure to receive the NanoVNA-H with version 3.4 printed circuit board.

You may be referring to the link that John posted but he corrected his post and said his NanoVNA-H has a version 3.3 printed circuit board. I have the same 3.3 ver PCB in my NanoVNA-H, and like John I am satisfied with its performance, but if I were ordering a unit today I would definitely try to get a NanoVNA-H with ver 3.4 PCB because of the additional performance enhancements for the same price.

You can review my posts #8810 and #8820 for some of the ver 3.4 PCB enhancements.

- Herb

OK calibration done again and appears about the same. I dont see any sharp spikes like I would have expected as you get away from the frequency the antenna is "tuned to" and it seems whatever frequency I set it to the SWR and reflection loss are high but not horrible like it should be. I know the TX output is good but in daylight will have to climb up to the antenna to do some testing.

I dont know what TDR is but that seems like something which I will wont to learn about.

Ill do more playing tomorrow

Disclaimer: I have nothing to gain by sharing this, I am a potential customer that’s all!

The service has a very interesting model! Could totally fix risk of credit card / bank account issues should it prove safe itself.

It works like PayPal in the sense of they have the link to your bank account or debit card.



I plan to use this system to pay for my Alibaba order.

Good Luck,

Seth

Herb,
The vna you showed via the picture you uploaded is different from the unit in the ebay listing you linked? The ebay add shows and older type unit with no case, and mentions it will come with a 350ah or 500ah battery.

Is that the correct link you ordered/received the new unit from? Thanks for your help....


--
Regards,
Chris

You can also use the Nano to check the coax in question.

Use dB S21 and see the attenuation. Compare to the listed spec from the mfg. If its more than a few tenths off, the coax is probably bad.

A badly installed connector can allow moisture ingress and ruin the coax in very short order. I just had almost 250 feet of 9913 go bad. Moisture had turned the shield to a powder and the center conductor was black. Run had almost 5x the attenuation of good coax.

I cut the ends off until the shield was good again and reinstalled new connectors. Loss was back in spec.

Also, ensure you've calibrated out the length of coax if you want truly accurate readings.

--Shane
KD6VXI

On Sun, Dec 29, 2019 at 05:27 PM, John Smith wrote:

Are the newest ones, the one with the plastic enclosure and fancy gift box? The same seller has those, the white, and the F versions too.
=========================================================

John,
In addition to sending the previous v3.4 photo attachment I should have answered your question about the "one with the plastic enclosure and fancy gift box". Yes it does come packaged like that but right now you can't tell if it has the version 3.4 PCB unless you buy directly from hugen's Alibaba store.

Hope that clears things up for you. If not compare the previous attachment photo I sent to the one you attached to your message #8806.

- Herb

I set this up and am convinced it's the best way to measure characteristic impedance.

You set up the Smith chart to find the first eighth wave resonance which for an open end line will be at the bottom center of the chart. Note the frequency on the top of screen. Change the frequency to a little below and to a little above that frequency. Note the capacitance displayed.

Then select phase and carefully adjust the marker until the phase reads 90 degrees, or as close as possible.

Then comes the hard part. You use the reactance formula, where X = 1/(2 * pi * frequency * capacitance). My calculator does this in a flash. Or use a reactance calculator or chart.

That gives X at the marker frequency. I get results that are within less than 1 Ohm of 50 Ohms on various cables.

A line that is short has a high frequency for 90 degrees. A long line does it at a lower frequency. The capacitive reading adjusts itself to satisfy the equation.

Better than my earlier method using a variable resistor.

The nanovna also has a TDR function which is excellent for finding
discontinuities in transmission lines.

Dave - W?LEV

--

*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*

Sorry, never mind. I just saw a Facebook post of someones "gift box plastic enclosure" has board version 3.3 like mine. Well, I'm happy with what I've got anyway. Good luck with the hunt.