Author Topic: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer  (Read 27229 times)

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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #150 on: August 05, 2018, 05:35:07 pm »
Strange thing is the MIN deviation shown seems quite repeatable.

When the SG is set to 1.88 kHz FM modulation, the Min value consistently shows 1.3 kHz deviation on the SVA.
When the SG is set to 2.88 kHz FM modulation, the Min value consistently shows 2.0 kHz deviation on the SVA.
When the SG is set to 3.88 kHz FM modulation, the Min value consistently shows 2.7 kHz deviation on the SVA.
When the SG is set to 4.88 kHz FM modulation, the Min value consistently shows 3.4 kHz deviation on the SVA.
When the SG is set to 5.88 kHz FM modulation, the Min value consistently shows 4.1 kHz deviation on the SVA.
When the SG is set to 6.88 kHz FM modulation, the Min value consistently shows 4.8 kHz deviation on the SVA.

I repeated the pattern starting at 1kHz, with 1 kHz steps and it is consistent.

Applying these rules results in a sensible value:
Over 5kHz deviation you can read the average value and divide it by 0.7 to get the correct deviation.
Under 5kHz take the MIN value and divide it by 0.7 to get the correct deviation.

So perhaps you can get the signal going then hit restart measurement and remember the value.

My Signalhound in analog demod mode shows +/- deviation values which are about 1% less than the SG setting, so I'm reasonably confident that the SG is outputting something sensible.
« Last Edit: August 05, 2018, 07:24:53 pm by hendorog »
 

Offline tautech

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #151 on: August 09, 2018, 12:09:07 pm »
New firmware for SVA1015X
V2.1.1.1.12a
https://www.siglentamerica.com/download/6912/
38.8 MB

Changelog
2018/8/8
1. Spectrum Analysis modeļ¼šImproved the stability of sweep and interface.
2. VNA mode: fasten the VNA sweep speed; expand the minimum span from 10M to 10 kHz.
3. Modulation Analysis mode: add trigger, optimize the modulation analysis algorithm.
4. Add user port number selection for web server.
« Last Edit: August 15, 2018, 10:52:12 pm by tautech »
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Online TheSteve

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #152 on: August 09, 2018, 01:24:12 pm »
When someone gets the actual Siglent cal kit it would be nice to see what S21 phase looks like with both the open and short connected after performing a calibration.
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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #153 on: August 09, 2018, 01:46:02 pm »
When someone gets the actual Siglent cal kit it would be nice to see what S21 phase looks like with both the open and short connected after performing a calibration.

Do you mean S11 phase? The S21 phase won't be measuring anything with an open and/or short connected.

Anyway, that can be done now, without waiting for the official cal kit. This is because the Siglent cal kit characterisation data is already installed in the analyzer. So any open short and load will show exactly the same trace as the official cal kit will - as the data pre-set in the analyser defines 'what they are'.

Anything else that you measure will show a different traces if you cal with different kits. But measuring the parts in the kits themselves will show the same traces as they just reflect the cal data in the analyser.
 

Online TheSteve

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #154 on: August 09, 2018, 02:43:42 pm »
When someone gets the actual Siglent cal kit it would be nice to see what S21 phase looks like with both the open and short connected after performing a calibration.

Do you mean S11 phase? The S21 phase won't be measuring anything with an open and/or short connected.

Anyway, that can be done now, without waiting for the official cal kit. This is because the Siglent cal kit characterisation data is already installed in the analyzer. So any open short and load will show exactly the same trace as the official cal kit will - as the data pre-set in the analyser defines 'what they are'.

Anything else that you measure will show a different traces if you cal with different kits. But measuring the parts in the kits themselves will show the same traces as they just reflect the cal data in the analyser.

Yes indeed, S11.

I was just wondering as the results I get with my Kirkby(not quite in spec kit) and a proper Agilent kit are of course different(with the proper defs entered/selected for each). 
« Last Edit: August 09, 2018, 02:47:55 pm by TheSteve »
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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #155 on: August 09, 2018, 02:47:30 pm »
When someone gets the actual Siglent cal kit it would be nice to see what S21 phase looks like with both the open and short connected after performing a calibration.

Do you mean S11 phase? The S21 phase won't be measuring anything with an open and/or short connected.

Anyway, that can be done now, without waiting for the official cal kit. This is because the Siglent cal kit characterisation data is already installed in the analyzer. So any open short and load will show exactly the same trace as the official cal kit will - as the data pre-set in the analyser defines 'what they are'.

Anything else that you measure will show a different traces if you cal with different kits. But measuring the parts in the kits themselves will show the same traces as they just reflect the cal data in the analyser.

Yes indeed, S11.

Ok, will do tonight and post some pics.
 

Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #156 on: August 09, 2018, 05:19:58 pm »
New firmware for SVA1015X
V2.1.1.1.12
https://www.siglentamerica.com/download/6912/
38.8 MB

Changelog
2018/8/8
1. Spectrum Analysis modeļ¼šImproved the stability of sweep and interface.
2. VNA mode: fasten the VNA sweep speed; expand the minimum span from 10M to 10 kHz.
3. Modulation Analysis mode: add trigger, optimize the modulation analysis algorithm.
4. Add user port number selection for web server.

Modulation is working much better. Deviation now works as expected.
Modulation rate also now works. Previously it showed a constant number IIRC.

This pic is with 0dBm input, AF modulation of 500Hz and FM modulation of 2kHz set on my old Marconi 2019A (uncalibrated)

The SA function shows channel power of about 0dBm, whereas the modulation function is showing carrier power of -3.42dBm so am not sure if that is showing an incorrect value or if I am just ignorant on something.

Changing the filter setting definitely makes a difference now.

Well done Siglent, a significant improvement there.



 
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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #157 on: August 09, 2018, 05:34:39 pm »
VNA function is clearly improved as well.
* As noted the sweep speed is about 5X faster. Now about 1 second.
* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.
* There are now three cal kits which can be selected: F503ME, 85032F, 85032B/E
* Modify cal kit is still disabled, and port extensions are also still disabled.
* Trace export is still missing. This is a big feature as it enables many things. It should support CSV and s1p files as a minimum.

All in all this looks much improved. Commendable in such a short time frame.

open, short and load traces for the default cal kit are attached

Edit: fix pics
« Last Edit: August 09, 2018, 05:49:07 pm by hendorog »
 
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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #158 on: August 09, 2018, 05:55:00 pm »
Here is a pic showing the post cal repeatability with 10x averaging turned on

The open is just an open SMA port - so no connector repeatability error.
The short is an SMA short - so that has connector repeatability error.

This is many minutes after calibrating and after several connection cycles for the various screenshots done earlier.

Note that the minimum scale is 1dB/div which needs to be fixed.

 

Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #159 on: August 09, 2018, 06:03:32 pm »
In summary I think the two big ticket items still missing are:
* Trace export function in CSV and s1p formats.
* Fix the VNA sweep to support frequencies below 10MHz.

I think the VNA function would be really improved by adding those two features. Also it would appeal to a wider audience and so generate more sales.
 
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Offline nautiboy

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #160 on: August 10, 2018, 04:00:24 am »
Thanks for testing and reporting on the update.  I saw it last night and was hoping it would fix the modulation analysis issues described earlier.  I briefly tried to install it, but it failed, possibly because I was trying to install the update over the LAN instead of via USB.  It *seemed* to work initially.  I was able to point it at the proper update file, and it seemed to load it, but then it said the file format was unsupported.  I set that to the side at the time because I had some other tests I needed to get done.   I was going to try the update again some time today after I dug up a USB stick in my pile of stuff. 

Regarding your comments about the "issue" with the VNA not going below 10Mhz ... I thought the specs actually stated that the VNA was only supported from 10Mhz and up.  Is there a particular reason you think this will eventually be "fixed"?   Of course I would love it if it went below 10Mhz, as that would allow usage on the bands below 30m.  I was figuring I'd have to get a return loss bridge so that I could at least do scalar measurements at the lower frequencies.  Which brings me to another question I had, which is whether it's possible to use a return loss bridge and still enable some of the network analysis measurements/calculations (similar to the reflection/vswr option on the SSA3K devices), or if I'd have to do the measurements/calculations by hand the "old fashioned" way?   

Also, I was curious about the EasySpectrum software.  The download page only lists it for the SSA3K devices and not for the SVA.  Does the same software work on the SVA or have they not released it yet for the SVA?

 

Online PA0PBZ

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #161 on: August 10, 2018, 04:19:57 am »
* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.

When tautech posted the changelog for this update he said "expand the minimum span from 10M to 10 kHz", so that is not minimum frequency unfortunately. I wouldn't keep up your hope too high, it is probably a limitation of the hardware.
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Offline PhilipPeake

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #162 on: August 10, 2018, 04:55:01 am »


Quote from: PA0PBZ on Today at 04:19:57 am


>Quote from: hendorog on Yesterday at 05:34:39 pm
* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.



When tautech posted the changelog for this update he said "expand the minimum span from 10M to 10 kHz", so that is not minimum frequency unfortunately. I wouldn't keep up your hope too high, it is probably a limitation of the hardware.



I think the coupler(s) may be the reason for the low er (10MHz) limit.

I am sort of surprised it works at that frequency.

Looks like a decent SA, but I am not really sure about the VNA part.
It misses the Ham market with its lower frequency limit, and misses the professional market with its upper frequency limit.
Its really over priced. Somewhere between free and $200 for the VNA option would seem about right.

Unless they can surprise us, and get the lower VNA frequency limit down to (say) 1.5MHz. The PCB material really limits the upper end.
 

Offline nautiboy

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #163 on: August 10, 2018, 04:57:38 am »
Successfully updated to the latest firmware using the USB. 

Modulation analysis does indeed seem to be fixed (or at least vastly improved).  The totally wonky demodulated signal display is now fixed (I really should've taken a screen capture before updating - the waveform was clearly messed up in very interesting (and physically impossible) ways). I see the correct demodulated waveform now.  And the deviation now appears to be giving the correct result.  Woot!  That makes my life much easier. 

VNA is indeed much faster now.  I do find it a little curious though that the span can be reduced to 10kHz despite that it seems the RBW is fixed at 10kHz (maybe I'm wrong and/or it's just a misleading display - if you go to RBW it shows 10kHz greyed-out) . 
« Last Edit: August 10, 2018, 04:59:46 am by nautiboy »
 

Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #164 on: August 10, 2018, 05:02:21 am »
* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.

When tautech posted the changelog for this update he said "expand the minimum span from 10M to 10 kHz", so that is not minimum frequency unfortunately. I wouldn't keep up your hope too high, it is probably a limitation of the hardware.

Oh yes you guys are both right. I misread that point in the changelog.

 I do hope it isnt a hardware limitation though. I am not sure what the problem is though - as with this architecture any phase sync errors in the plls are cancelled out.

 I havent played with the scalar side yet, I will post a pic of it .
 I will also have try the easy spectrum software.

Sorry typing this on phone, am replying to nautiboy as well.
 

Offline tautech

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #165 on: August 10, 2018, 05:08:29 am »
Successfully updated to the latest firmware using the USB. 

Modulation analysis does indeed to be fixed (or at least vastly improved).  The totally wonky demodulated signal display is now fixed (I really should've taken a screen capture before updating - the waveform was clearly messed up in very interesting (and physically impossible) ways). I see the correct demodulated waveform now.  And the deviation now appears to be giving the correct result.  Woot!  That makes my life much easier. 

VNA is indeed much faster now.  I do find it a little curious though that the span can be reduced to 10kHz despite that it seems the RBW is fixed at 10kHz (maybe I'm wrong and/or it's just a misleading display - if you go to RBW it shows 10kHz greyed-out) .
Hoping for some clarity on the minimum BW later today.
We can all see 10 KHz listed in the changelog and based on hendorog's findings with my unit I sent Siglent an email yesterday looking for an answer on this issue.
EDIT
Reply from Siglent.
My misunderstanding, 10 KHz IS new Span, improved from 10 MHz.

* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.

When tautech posted the changelog for this update he said "expand the minimum span from 10M to 10 kHz", so that is not minimum frequency unfortunately. I wouldn't keep up your hope too high, it is probably a limitation of the hardware.

Oh yes you guys are both right. I misread that point in the changelog.

 I do hope it isnt a hardware limitation though. I am not sure what the problem is though - as with this architecture any phase sync errors in the plls are cancelled out.

 I havent played with the scalar side yet, I will post a pic of it .
 I will also have try the easy spectrum software.

Sorry typing this on phone, am replying to nautiboy as well.

Then again why would it even be mentioned in the changelog as something Siglent has addressed ?
I'm hoping that it's just a grammar/translation thing.
« Last Edit: August 11, 2018, 05:37:04 am by tautech »
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Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #166 on: August 10, 2018, 05:44:58 am »


Quote from: PA0PBZ on Today at 04:19:57 am


>Quote from: hendorog on Yesterday at 05:34:39 pm
* Start freq for VNA still seems to be 10MHz minimum. I have tried various things but I don't think that has been resolved with this update.



When tautech posted the changelog for this update he said "expand the minimum span from 10M to 10 kHz", so that is not minimum frequency unfortunately. I wouldn't keep up your hope too high, it is probably a limitation of the hardware.



I think the coupler(s) may be the reason for the low er (10MHz) limit.

I am sort of surprised it works at that frequency.

Looks like a decent SA, but I am not really sure about the VNA part.
It misses the Ham market with its lower frequency limit, and misses the professional market with its upper frequency limit.
Its really over priced. Somewhere between free and $200 for the VNA option would seem about right.

Unless they can surprise us, and get the lower VNA frequency limit down to (say) 1.5MHz. The PCB material really limits the upper end.

Yep, I forget that this has a tiny chip coupler in it. Because it has a factory cal it always looks good, and you never see the directivity of the actual device. There is a little bit of noise creeping in close to 10MHz on those traces I posted yesterday, so you are probably right.

I also thought that it would miss the Ham market, but as nautiboy mentioned there is the scalar option with the tracking gen so it's not so bad.

There is also potential for making a simple external transverter. If they add the ability to export the measurement data from Port #2 then that could be used with PC based calcs to cover the full range.

The upper end is locked in for this device so it wouldn't make sense to use a high frequency PCB material. But there will likely be higher frequency units to come as the base platform is so similar to the SSA.

 

Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #167 on: August 10, 2018, 05:49:33 am »
Then again why would it even be mentioned in the changelog as something Siglent has addressed ?
I'm hoping that it's just a grammar/translation thing.

I thought they had changed the minimum possible start freq of the sweep - and that is still 10MHz after the update.

But they have actually changed the minimum span in VNA mode - which was 10MHz, and is now changed to 10Khz.

So yeah, that was an oops on my part.

 

Offline tautech

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #168 on: August 11, 2018, 05:50:16 am »
Mouse, keyboard and auto power ON demo video from Jason (Siglent USA)
~4.30 minutes

https://www.siglentamerica.com/video/sva1015x-touchscreen-mouse-keyboard-and-power-on-line-features/
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Online PA0PBZ

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #169 on: August 11, 2018, 06:08:21 am »
Mouse, keyboard and auto power ON demo video from Jason (Siglent USA)

So boot on power on, keyboard and mouse... What was he demonstrating, a PC?  ;)
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Offline nautiboy

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #170 on: August 11, 2018, 09:30:47 am »
Yeah, pretty much a computer.   :)  Not shown in the video, but I love the fact that it's running a VNC server.  I can just point my VNC viewer at it and monitor and control it completely remotely.   You can do something similar by pointing a web browser at its webserver, but I've found I like the native VNC interface better.  I can sit on the couch sipping scotch monitoring and controlling the analyzer up in my office.  Heck, since I can VPN into my network from anywhere, I could be sitting at the beach running tests.  Now why one would actually want to be running spectrum analyzer tests while on the beach, well that's another question, though I ask you whether you'd rather run them in a cramped, hot office or sitting out on the beach.  8)

 

Offline rf-loop

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #171 on: August 11, 2018, 05:19:51 pm »
Mouse, keyboard and auto power ON demo video from Jason (Siglent USA)

So boot on power on, keyboard and mouse... What was he demonstrating, a PC?  ;)

Even with my bad english he tell clearly what he demonstrate. You can use mouse and keyboard.

Also perhaps he is accidentally demonstrating something what looks weird or like bug.

Time position 59s - 60s happen something what I can not understand without further info. (Perhaps Jason can tell?)
as can see there is RBW 1MHz and attenuator 20dB (and ref level 0dBm) and trace is around -60dBm what is ok.
Then his hand do "something"
and after then
Same RBW but now attenuator 30dB. look now where is 0dB (left side scale) There need read now reference level 10dB (but there read 1.0dBm - why?)
But then. If you look noise level now, it is around -40dBm. 10dB attenuator step produce noise level 20dB step. It is weird.
First it looks like step is 10dB but if look moved trace position and scale. It have stepped up 20dB.
It looks weird if do not know what happen there what can not see in video. Are there edited some things out from video just in this point or what happen.
I do not have SVA so I can not repeat this...



ETA:

Video screen shots

ETA2:

Finally after more analyzing video  these bit blurry screens it looks like it is ok.
Left scale after change from 20 to 30dB attenuator and small vertical adjust
left scale must be from top to down...   1, -9, -19, -29..... etc.  (not 1, 0, -10, etc...) So there is not bug in left side scale. Also if there is 0 it do not have - sign.
So this was wrong alarm.  |O :palm:
« Last Edit: August 12, 2018, 08:38:17 am by rf-loop »
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Offline tautech

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #172 on: August 11, 2018, 09:53:30 pm »
rf-loop
What you see is a product of fast touchscreen demonstration with NO clear defined intent. (like some old Dave video of fast turning of knobs)

With such a swipe of a finger up and down the display both Ref and Atten levels can be affected and Jason's actions show this well.
But, when a finger is placed on the sweep waveform and raised or lowered with clear intent only the Ref level will change.
hendorog and I have just explored this issue without any attempt to adjust touchscreen properties from factory default.
Until I explore how user touchscreen settings might affect what you see in Jason's video I cannot call it a bug, only fingers working faster than mind.


Not ideal I know for an SA but a wireless mouse and keyboard works just fine with SVA.

I have my SVA back now but lost my SSA to hendorog .......again.  :scared:
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Offline rf-loop

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #173 on: August 12, 2018, 01:07:06 am »
rf-loop
What you see is a product of fast touchscreen demonstration with NO clear defined intent. (like some old Dave video of fast turning of knobs)

With such a swipe of a finger up and down the display both Ref and Atten levels can be affected and Jason's actions show this well.
But, when a finger is placed on the sweep waveform and raised or lowered with clear intent only the Ref level will change.
hendorog and I have just explored this issue without any attempt to adjust touchscreen properties from factory default.
Until I explore how user touchscreen settings might affect what you see in Jason's video I cannot call it a bug, only fingers working faster than mind.


Not ideal I know for an SA but a wireless mouse and keyboard works just fine with SVA.

I have my SVA back now but lost my SSA to hendorog .......again.  :scared:

Yes but what ever user do with his fingers final steady result must not be wrong. Of course dsoing something fast there can be  some errors until  all is updated in screen but this is not like it, this error stay.
Now result is that noise trace is roughly 10dB too high if look left side scale numbers.
As can see. image 2  there is left side scale. 1 , 0, -10, -20, -30, -40*, -50, -60, -70, -80,  -90 
*Noise trace is here (around -40dBm)
Then left top corner there read Ref 1.0 dBm
How it is possible there is left side scale 0dBm to 1dBm one division when setup is 10dB/div. Least this is not ok.
It is wrong without any doubt.


It looks like all is ok IF left side scale is  1 , -9, -19, -29, -39, -49*, -59, -69, -79, -89, -99  (I do not have SVA so I can not look more deep)
ETA:When analyzing a little bit blurry video, pretty sure it is this.

Perhaps it is old FW ???  or is this issue still there?  So this is nice if we know it.

I know Jason is just demonstrating mouse and touch and keyboard. Not testing other things.

But when I look this video first time, immediately I see something what I did not expect with my experience and after then I replay it again and yes, noise level hop 20dB when attenuator change 10dB. 

(later look more carefully and find that if correct left side scale, it is ok)
After then I look left scale and ... oops ... how first top div can be 1dB when scale is 10dB  !

My suspect is that in this FW version what ever he use,  it looks like there is bug in left scale numbering.
It is nice to know if this is repaired in later FW-
« Last Edit: August 12, 2018, 08:44:14 am by rf-loop »
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It is much easier to think an apple fall to the ground than to think that the earth and the apple will begin to move toward each other and collide.
 

Offline hendorog

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Re: Siglent SVA1015X 1.5GHz Spectrum & Vector Network Analyzer
« Reply #174 on: August 12, 2018, 06:43:35 am »
Quote
It looks like all is ok IF left side scale is  1 , -9, -19, -29, -39, -49*, -59, -69, -79, -89, -99

I am going to go out on a limb here and say that it does show these values after the swipe.

I went back to the video and the 0's are more clearly 0's before the adjustment. After the adjustment they don't look as clear and so that makes me think that they are actually 9's.

Image attached shows two numbers. One from after change on the top, and before change on the bottom.
(These aren't from the same position in the grid, I just grabbed two which looked clear.)


I think top value is -19 and bottom value is -10

 


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