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can anyone tell me what the WILTRON 6407 RF ANALYZER does,is it the same as a vna,or more,cheers.

Just a casual observation / opinion. The device looks to be rather expensive for typical ham use to me,
Unless of course you require testing capabilities in the 4.4 GHz ranges. The so called classic models
like the Nano VNA H4 operate up to about 1.5 GHz and are less than half the price. Other than that
I am not familiar with that particular device.

"or" is left in the question :)

How do you update or does your nanovna-H4 look like the attached video?


Link to get FW Hugen:

Well, Ollie, now you have done it.
I have the Tiny SA and NanoVNA-H4.
I have used them intermittently for some time, with the original firmware.
For some reason, I decided this weekend to update the firmware for both devices.
I used the Update instructions by K5DW, using the stm32cube program.
I started with the tinySA and following the directions, it updated perfectly.
Looking at other instructions for updating the NanoVNA, all were done in the dfu mode using the DfuSE software.
When I went to download it, ST Micro indicated it had been replaced with the 32cube software.
So, I used the 32cube program for the NanoVNA also.
I think my mistake was to use the .dfu file the first time instead of the .bin file.
In any case, now I have a black screen, and the computer will not recognize the usb connection, claims it failed last time.
Now I have been able to put the unit in the dfu mode by pressing the wheel while turning on, and the computer recognizes it.
I tried to install the .bin update and an earlier update to no avail using the 32cube software.
So I went to the DfuSE program and installed the .dfu file using that software.
I managed to get it connected and asked it to install the latest .dfu file, which it did (I think).
However, I still have the black screen and no usb in the normal mode.
Have I had it, and needing a new one, or is there some hope of salvation?
Any and all help greatly appreciated!
73
Fred
WD9HNU

On 2022-05-22 07:47:+0100, you wrote:

I see adverts for the SV4401A 4.4 GHz, 7-inch VNA from JNCRADIO, with N
connectors.

Connecting to it might be tricky "witch can be used to connect DUTs with SMA interfaces." ;-) Just gotta find that nearest coven, I guess.

~R~
72/73 de Rich NE1EE
The Dusty Key
On the banks of the Piscataqua

I see adverts for the SV4401A 4.4 GHz, 7-inch VNA from JNCRADIO, with N
connectors.





- Does anyone know anything further about this device?
- Has anyone bought one?
- What Windows software supports it?
- Where are the firmware updates to be found?

I have one on order, but I can return it if it's not good.

I see nothing in the group messages or the Wiki.

Thanks,
David GM8ARV
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

Just use the 'measure / cable' function from the menu; it should work
fine. It should report the impedance to be about 75ohm, and the length and
loss of the cable.
You do need to set the VF first. But note that true VF often varies by a
few percent from published design values, so you can only expect a length
measurement within a few percent.

Using the NanoVNA to measure length of RG-6U cable, is it recommend to use a matching transformer (50Ω to 75Ω) or is that really just a moot issue? I have all the specs otherwise, such as VF.

Thanks,
Brian D
KF6BL

Connect with a small coupling cap?!?
Dg9bfc sigi

Am 20.05.2022 21:03 schrieb Gerard <kabupos@...>:

Hello,

I’ll start with one simple thing (see picture)
Take the features of only one of the 45M15A 2-pole filter
How to have this measurement at -3DB

If I cascade 2 filters, the 2nd cannot amplify the loss of the first????

My two questions are:
How to have a maximum loss of 3 db using a single filter? Schématic?

What is the method to pair 2 filters 2 poles to have one of 4 poles.?
please put a specific example.

Thank's

On 5/20/22 11:20 AM, Jim Allyn - N7JA wrote:

On Fri, May 20, 2022 at 10:57 AM, Jim Lux wrote:

If you have Windows, download Elsie from Tonne Software.

Windows is not necessary. Elsie runs in Linux in WINE just fine! I think there is something similar for Mac, too, so it will probably run there, too.

I've run it with Parallels (but that's just running Windows in a VM on Mac). And with the new Macs based on a non x86 CPU, I don't know if one will be able to do that.

On Fri, May 20, 2022 at 10:57 AM, Jim Lux wrote:

If you have Windows, download Elsie from Tonne Software.

Windows is not necessary. Elsie runs in Linux in WINE just fine! I think there is something similar for Mac, too, so it will probably run there, too.

On 5/20/22 9:52 AM, Gerard wrote:

Hello

So i don't speeak English, i use reverso
Thank you for your answers.
I am at the beginning to break my head on the wall to understood how that work


I really have a hard time setting up and understanding how this filter works.
Before talking about 4 pole filter with a cascade of 2 2*poles filters,, I will simplify to a 2 pole filter all made (Type motorola 20j26 on Ebay or 45R15AZ on Alie Express (I have a lot of each))
If I test this filter alone with a generator and an oscilloscope we see that we have a maximum signal at for example 44.998 and 45.006 Mhz
If we move to 45mhz, the signal is much weaker.

That is exactly as expected - what you have is two filter sections, one tuned to 44.998, the other 45.006. The combination of the two is fairly broad, but there's a dip in between.

At one center frequency, there's no attenuation from one filter, and some from the other.

At the other center frequency, the same is true.

At the center, you're seeing both filters attenuate, so you get a dip.

If you bring the center frequencies together, there's a point where they just even out. If you bring them farther apart, you get two distinct peaks.

In all cases, the filter rejection "far out" is basically twice what a single filter can do.

If your design needs, for example, 100 dB rejection "out of band", and your filters can do 50 dB (far away from center), then you can stack 2 of them. But say your filters are 5 kHz 3dB bandwidth. If you directly cascade them at the same frequency, the -3dB point will be narrower - you'll be -6dB at the bandwidth (+/- 2.5 kHz).

So what you do is tune them a bit apart.? Then as you sweep, one filter is coming up to it's peak while the other is falling off.

If I place the filter in the assembly of my Ubitx homebrew, and I make a measurement I have the same behavior by putting the generator in input of the 1st amplifier (behind the mixer) and looking at the oscilloscope in output of the filter
(Clocks are disabled because plug-in module)
I wonder if the measure is right?
Actually, I’m gonna go back to zero to figure it out.
I need a test model diagram.
I am not an RF engineer and I really do not see how to have a "flat" part between for example 44993 and 45.007 which will make about 14 Khz of bandwidth.

Getting it "flat" is really tricky - and might not even be possible with 2 filters. That is, if you set the filters far enough apart that you get the bandwidth, you get a dip in the middle, because the peak is sharp, compared to the desired bandwidth.

This is the challenge with filter design in general - as the desired percentage bandwidth increases, while keeping low loss in band, and good rejection out of band, you need more and more sections.

If you have Windows, download Elsie from Tonne Software. The student version is free and you can experiment with the number of sections, and see what happens with Butterworth, Chebyshev, Cauer/Elliptical in a sort of interactive way.

Also, despite my module tested at the nanovna which had a nice curve, (see previus post) I also have the same behavior.
So we’re back to zero?
No simple for me.

cdt

Hello

So i don't speeak English, i use reverso
Thank you for your answers.
I am at the beginning to break my head on the wall to understood how that work


I really have a hard time setting up and understanding how this filter works.
Before talking about 4 pole filter with a cascade of 2 2*poles filters,, I will simplify to a 2 pole filter all made (Type motorola 20j26 on Ebay or 45R15AZ on Alie Express (I have a lot of each))
If I test this filter alone with a generator and an oscilloscope we see that we have a maximum signal at for example 44.998 and 45.006 Mhz
If we move to 45mhz, the signal is much weaker.
If I place the filter in the assembly of my Ubitx homebrew, and I make a measurement I have the same behavior by putting the generator in input of the 1st amplifier (behind the mixer) and looking at the oscilloscope in output of the filter
(Clocks are disabled because plug-in module)
I wonder if the measure is right?
Actually, I’m gonna go back to zero to figure it out.
I need a test model diagram.
I am not an RF engineer and I really do not see how to have a "flat" part between for example 44993 and 45.007 which will make about 14 Khz of bandwidth.

Also, despite my module tested at the nanovna which had a nice curve, (see previus post) I also have the same behavior.
So we’re back to zero?
No simple for me.

cdt

On 5/20/22 6:24 AM, alan victor wrote:

Motorola provided 4 pole filters from matched 2 poles. The dot mark on each xtal must face each other. At their junction a proper shunt C to gnd is added. This sets the coupling factor for the 4 pole. The xtals were delivered including the cap setting the coupling. Terminations for the filter pair were usually complex, RC, A COUPLE OF k shunt a few pF. You will need to add a LC network to provide from 50 ohm source and load.
Alan

If anyone wants to fool around with a sort of idealized "two resonators in series" and how you can stagger tune to get a "bandpass" see the attached spreadsheet. There's another sheet with 4 resonators..

You can change resonant frequency and Q (the equation's not perfect, but it's close)

Nor does it take into account things like coupling, etc.

But you can see how you can cascade resonators to get a fairly flat bandpass characteristic, and you can interactively "tune" the stages (oh, just like tuning a cavity filter with a VNA)

Motorola provided 4 pole filters from matched 2 poles. The dot mark on each xtal must face each other. At their junction a proper shunt C to gnd is added. This sets the coupling factor for the 4 pole. The xtals were delivered including the cap setting the coupling. Terminations for the filter pair were usually complex, RC, A COUPLE OF k shunt a few pF. You will need to add a LC network to provide from 50 ohm source and load.
Alan

Saver reads the values from the nano as they are. If the nano is
calibrated, Saver gets calibrated values. If you reset or disable the
calibration on the nano, Saver will get uncalibrated data. Saver has no
way of knowing which it is.

Any calibration done in Saver is done 'on top of' the data from the nano.
So at first glance it would seem that turning off calibration in the nano
would be the right thing to do when calibrating within the Saver app. And
indeed this does work very well, at least for some of us. The catch is
that Saver's software wants to see well-behaved data points, within the
expected data range of -1 to 1 (if I remember correctly). But some nanos,
due to variations in component tolerances in the nano hardware, will
sometimes emit data values a bit outside that range. Save does not deal
with this, and will crash or otherwise misbehave.

So the Saver authors recommend calibrating the nano (usually over a broad
freq range that encompasses your needs) to avoid this issue. You can then
do additional layers of calibration in Saver, including the very useful
feature of multiple segments to multiply the number of points.

But if you try it on your nano and it works correctly for your scenario,
using Saver with the nano's calibration turned off is a good (better?) way
to go. It is then calibrating raw data, and there is no concern about
compatibility of the frequency range used to calibrate the nano vs that
used in Saver.

Jim,

filters are 45R15AZ from Aliexpress, but no datasheet found. Sold as equivalent to 45M15A?
Nothing specified on couplage value.
cdt

On 5/19/22 7:51 AM, Gerard wrote:

re,

I’m back on track. I wonder, should we not focus too much on the gain curve, but rather improve the loss curve?
see attachement
cdt

The S11 (return loss)?

Most filters have a terrible return loss outside their passband.

What you need to ask is "what's driving this" - will the reflected power out of band cause a problem? (i.e. make an amplifier unstable) - generally not.

And, because S22 is likely similar, will the next stage care about the input having a poor match out of band (i.e. become unstable).

If you're running into/out of a mixer, the usual thing is to put some resistive attenuation (or a circulator if you're at microwaves) - a 3 dB pad means that no matter how bad the filter is, the mixer only sees -6dB at worst.

The fact that the match varies "in band" is already taken into account in the S21 measurement - it's normalized to a ideal 50 ohm source, so the fact that the filter reflects 10% of the power (-10dB) (transmitting 90% into the filter) at some frequencies and 1% at others (-20dB, transmitting 99%) is accounted for in the S21 measurement.

10 dB reflected corresponds to -0.5 dB transmitted.


A device that reflected -10dB at some points and -20 dB at other points, when looked at in the transmitted sense (leaving aside any absorption internally) would look like varying between -0.5 and -0.004 dB gain.? Real filters have some loss inside the filter, so the gain is typically a bit flatter than you'd expect just from the S11 and S22.