Eric asked about use cases for frequecies >10GHz.

Well, here is mine! I am, among other things, a satellite DXer and interested in satellite TV reception.

In order to get fringe reception going and to maintain my dishes and equipment, I own not one, but two "Schwaiger SAT-Prüfgenerator SPG 101".

These small devices were used back in the analogue satellite receptions days to simply test if the LNB is working! The device emits a composite video test image composed of a simple grid at exactly 11.288 GHz.

If you could receive the test image with your analogue receiver, it meant that the LNB was OK and you had a fault somewhere else or misaligned dish.

With the TinySA Ultra I can now test if the SPG 101 iitself is working!



It seems, however, that the TinySA Ultra has some serious frequency deviations: instead of 11.288GHz, the signal is shown at 10.4139GHz. Not a big issue for me - I am happy to be able to "see" what is going on at all!

Anyway, I checked with a field meter, to make sure if the SPG 101 was not off:



The meter puts the centre frequency at 11.2815GHz, which seems close enough for me, considering the age of the SGS 101.

As a side note, I modified my second SGS 101 and added a composite video input. The IC used inside the device has actually the option to either generate a test pattern (as used by the SGS 101) or to upconvert a composite video signal. This allows me to broadcast composite video at 11GHz at a distance of around 1-2m.

So yes, it is great that the TinySA Ultra ventures into this frequency range, even if it not able to really measure anything. The mere possibility to just be able to see what is going on is amazing for such a cheap device.

I presented the SGS 101 on my blog in the past, for those interested:




Cheers,
Vitor

On Sun, Dec 25, 2022 at 04:10 AM, Vitor Martins Augusto wrote:

It seems, however, that the TinySA Ultra has some serious frequency deviations: instead of 11.288GHz, the signal is shown at 10.4139GHz.

Vitor,
A TV modulation is typical a broadband signal and as you know (you did read the wiki page on Ultra mode?) this could create some problems.
Can you disable CONFIG/SPUR REMOVAL and try again what you see? After disabling you should see the 11.288GHz signal at multiple frequencies, of which, hopefully, one is 11.288GHz
Can you post a screen photo with spur removal disabled for educational purposes?
?
--

Hello Eric,

I did read the Wiki and I do know about TV modulation.

Anyway, here is a new picture showing Trace 1 as LIVE with SPUR REMOVAL diabled and Trace 2 as HOLD.with SPUR REMOVAL enabled:



As can be seen, with SPUR REMOVAL disabled, some additional signals become visible. However, only one is apparently an harmonic! This picture shows the spectrum with the SGS 101 switched off:



This is not a critizism at all, nor am I complaining.

Also, I did not carry out any calibration, yet (but other measurments are correct frequency-wise, for example the 300MHz test signal from my HP8594E).

Let me know if you want me to test something else.

Regards,
Vitor

Viror
Thanks.
The frequency difference you saw is 2.8%, that must also be visible at much lower frequencies. Can you try?
--

I own some professional measuring equipment for frequencies up to 28 GHz, including a couple of microwave RF generators. I return home on Tuesday and can check the harmonic frequency deviations on the TinySA ULTRA more closely.

Mike

Eric,

I am confused.

I used my SMA 35-4400MHz device with my software and generated & measured the following signals:

Generated -> Measured

Here the same signal measured by the TinySA Ultra:

On Sun, Dec 25, 2022 at 07:52 AM, Vitor Martins Augusto wrote:

Can it be that the modulation of the signal from the SGS 101 causes the strange behaviour on the TinySA Ultra?

Could, the ultra mode works best on narrow unmodulated signals. I do not have the tools to test above 6GHz
?
--

Vitor

I will let it charge fully and test again.
Meanwhile I found my other SGS 101, tested it and the TinySA Ultra shows the frequency at 10.4169GHz, so about the same offset as the other SGS 101.
Again, all other measurements made with a simple non-modulated signal generated by the SMA 35-4400MHz (using 3rd harmonic) will be measured at the correct frequency by the TinySA Ultra, while other devices of mine will measure the SGS 101 at the correct frequency, as well.
I have no clue what is going on, but don't worry too much. It is just an oddity.
Up to now I was limited to measure up to 6GHz (with low-cost devices), so being able to go up to 12GHz is amazing.

开云体育

Hi All,

As promised I did the 10G horn test and yes, it worked. The markings on the horn said 10.535G and the Ultra measured 10.542G. I'd say that was pretty darn good.

As you can see in the pic below, this is what comes up when turned on. Can anyone explain? Thanks.

Mike C. Sand Mtn GA

I always worried that I fry the front end of my Tiny SA.

So I created a 0dbm signal on 10.4Ghz ( measured with a calibrated power meter from work through a 10.4Ghz band pass filter) and measured it with the SA. It showed -34to -35dbm on both units. I then adjusted the level offset by -35dbm and now the SA reads 0dbm +- . this permits me to make visually sure I do not overdrive the input.


John

Its in zero span mode
Do PRESET/LOAD STARTUP
--

Hi,?as promised, I did some frequency accuracy measurements on the TinySA ULTRA today.

I used the latest firmware v1.4-8, SA calibrated to 800 MHz, no frequency corrections, span 20 MHz, RBW and VBW set to Auto. Below 800MHz the SA was physically connected via an attenuator to the RF generator, above 10GHz the SA had only a short piece of wire on the SMA input for reception.

The radiated CW energy was -36 dBm below 800 MHz. And below -2 dBm above 10 GHz. I used a calibrated and verified Wiltron 20 GHz RF generator, below 800 MHz a 3 GHz HP RF generator, and for onsite verification an Anritsu MF2413B a 27 GHz GPSDO - stabilized frequency counter.

Results are as follows:
Frq: 656 MHz









11.000 000? GHz??
3rd SA harmonic











15.000 000 GHz
5th SA harmonic











20.000 000 GHz
5th SA harmonic











Setup ...








Mike, S51KQ

Any findings from the test?
--

Erik, the frequency is more accurate than I ever expected (I didn't see an error to 5 decimal places even on 5th harmonic). Very good, thanks also to your firmware!

That looks great and matches my experiements with the ADF4351 based signal generator using harmonics up tp 12GHz.

The problem I experience with my SGS 101 is certainly not caused by the TinySA Ultra.

Because I lack any other equipment to directly measure the signal produced by the SGS 101, I need to use a Ku-band universal LNB to downconvert.

On Wed, Dec 28, 2022 at 03:23 AM, Vitor Martins Augusto wrote:

It would be interesting for me to measure this frequency with some other device,

Can't the Ultra see the LO of the downconverter?
?
--

I made a new test. This time I used an LNB with two outputs. One is connected to my field meter (which powers the LNB), the other is connected (via a DC blocker) to the TinySA Ultra.

I set the field meter to 0MHz IF frequency, so that the downconverted frequency is shown, instead of +9750/+10600 MHz.

The field meter shows the signal at 1538MHz (=11.288MHz) and again the TinySA Ultra shows the same signal (measured simultaneously) at 1411MHz.





Connecting the TinySA in line with a sat receiver shows all transponders at the correct frequencies.

I really think that the SGS 101 messes up the TinySA somehow and by now I trust the TinySA more than the SGS 101!