Re: Tiny ULTRA. Scan made with in bundle antenna. is it a normal spectrum?
Copy that and thank you so much.
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My test are to be sure the system is working correctly since I'm thinking about using it with a TEM Cell for EMC precompliance.
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Unfortunately I'm getting a strange resonance no matter what at around 700Mhz and testing more than one product.
I would like to be sure that the problem is not related to acquisition system.
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Thank you so much
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NH
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Re: ZS-407 Spurious Signals
The worst spur is solved in my test setup, next I noticed some smaller spurs and now trying to get rid of these too
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Designer of the tinySA
For more info go to
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Re: Tiny ULTRA. Scan made with in bundle antenna. is it a normal spectrum?
WiFi is often hopping frequency and you need to disable spur reduction to better see it.
But with disabled spur reduction you will also see all kind of mirrors and spurs when doing such a wide scan.
Another option is to do a narrower scan around 5.5 GHz? (span 200 MHz) and enable MAX HOLD
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Did you read the page in the WiKi about the Ultra mode? I assume as you are using the Ultra mode, so you know when the Ultra mode will fail
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Designer of the tinySA
For more info go to
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Re: Tiny ULTRA. Scan made with in bundle antenna. is it a normal spectrum?
Good to know!
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My only concern is why I'm not getting something around 2.4Ghz from my wifi router...
NH
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Re: Tiny ULTRA. Scan made with in bundle antenna. is it a normal spectrum?
Yes, what you detected is quite normal these days.? You're fortunate that's all you detect!? Even here in the county between two hogbacks in N. Colorado where we see no cities or development, I've got a whole bunch more.
Dave - W?LEV
Hi guys,
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Calibrated and did all the things necessary to run it correctly with ultra path enabled.
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Scanned my office with the in bundle antenna and there are for sure both 2.4Ghz and 5Ghz wifi.
The 5Ghz is not present at all and the nearest frequency near the 2.4Ghz is 2.16.
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Is it a normal behavior?
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Thanks
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Tiny ULTRA. Scan made with in bundle antenna. is it a normal spectrum?
Hi guys,
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Calibrated and did all the things necessary to run it correctly with ultra path enabled.
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Scanned my office with the in bundle antenna and there are for sure both 2.4Ghz and 5Ghz wifi.
The 5Ghz is not present at all and the nearest frequency near the 2.4Ghz is 2.16.
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Is it a normal behavior?
?
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Thanks
?
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Re: Measurement problems, strange step noise floor behavior between 600-800kHz
In my rush to try to duplicate the test, I too neglected to set my scope to x1. I should have noticed the 20dB discrepancy. <red face>
toggle quoted message
Show quoted text
On Jan 21, 2025, at 6:07?PM, lschafer@... wrote:
? Thank you so much! You are absolutely correct! Of course, the scope was still set to the 10x probe endorsing to increase sensitivity on the TinySA.
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I am totally embarrassed now and feel sorry to have wasted your time. After re-calibration all problems regarding my questions have resolved.
Nonetheless, I was able to hand-calibrate the TinySA with a -20dBm sensitivity difference across the entire range.
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Thank you again
Lutz_._,_._,_
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Re: ZS-407 Spurious Signals
Thank you, Erik. Just to provide additional context, this is using FW 1.4.193, after two calibrations. The signals are there with LNA on or off and Ultra mode enabled or disabled. The signal levels - without an antenna and in a quiet RF environment - are about -74 dBm, about +52 dBm above my -126 dBm noise floor using 200 Hz RBW.?
FYI - many in my field are using the TinySA as a valuable tool for our work. I have had one (actually several) since they first came out and have developed software to control it for our specific needs. It is an amazing little device! Thank you for your efforts!
~ Otto
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Jeff? So would you take a request for (e.g.) a 0dBuV level signal to be referring to the generator EMF setting or the terminated PD ?Tip? Correct answer is its differently defined in Japan to USA and Europe is forced to clarify 
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Maybe try building an EMI tent from such a fabric:
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Chris
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On Tue, Jan 21, 2025 at 02:03 PM, <nighthawk.eng@...> wrote:
Maybe grounding everything to the house earth could be a good or a terrible wrong idea?
It could help? The conductive tent is a must?
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A TEM cell acts like a terminated shielded cable with the device under test between the shield of the cable.? An enclosed TEM Cell or GTEM can be used in a noisy environment as long as it has proper power and cable filtering.
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The TBTC2 is a stripline TEM cell with open sides and cannot be used effectively in an environment with high ambient for radiated emissions testing.? For high ambient environments, it needs to be located in either a shielded enclosure or conductive tent, neither of which is cheap.??
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E-Field and H-Field probes are another option for locating troublesome emissions, especially at 700 MHz.? If you see a 20 dB reduction in levels with the probe, you will see about the same reduction during compliance testing.? Just be careful to rescan the entire frequency range after any EMI fix.? Fixing one frequency can sometimes be detrimental to other frequencies.
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Herb
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Yes, dBuV i and dBuV/m is a standard for EMC like EN55032 used for multimedia devices.
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At 50 Ohms, there is an offset of 107, which suggests it may be relatively straightforward to manage.
Additionally, simplifying the process by including units of measurement (e.g., MHz, dBμV) in the first line of the CSV file can enable the system to automatically recognize the data upon future reloads.
Omitting units from the CSV may cause issues, particularly if the file name does not clearly reflect its contents.
The TinySA is an impressive product, but with a few adjustments, it could reach an even higher level of excellence.
My 2 cents
NH
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dBuV has long been the most inconsistent, confused, annoying and useless metric in RF Tech
That may be true in your experience, but for both military and commercial compliance testing, dBuV/m
for radiated measurements and dBuV for conducted measurements are the standard units.
dBuV is fine and well defined, it is dBu (ie without the V) that is confusing and inconsistent. Jeff
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Re: ZS-407 Spurious Signals
Otto,
Let me see what can be done to get rid of these
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--
Designer of the tinySA
For more info go to
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Re: ZS-407 Spurious Signals
On 22/01/2025 03:24, Otto Schellin via groups.io wrote: I just received my ZS-407 from R&L Electronics. I do frequency coordination for
large events and the most common frequency range for wireless devices is in the
470 MHz to 608 MHz UHF TV band. I set the ZS-407 for a start frequency of 470
MHz and a stop frequency of 608 MHz. The RBW was initially set for auto. With no
antenna on the 407 it was just showing a noise floor that was around -90 dBm.
When I changed the RBW to 100 kHz, it displayed a spurious signal around 533.8
MHz. As I drilled down into this signal and reduced the RBW even lower, it
turned out to be two very narrow bandwidth spikes at 533.725 MHz and 533.775
MHz. My older TinySA Ultra with the exact same settings does not display these
signals. I also tuned my Icom IC-R30 to those two frequencies in CW mode and
confirmed that no signals were received. Can anyone else see these “birdies” on
their ZS-407 or is it just mine?
- Otto
_._,_._,_ Otto, Here, with a span from 555.7 to 533.8 MHz, and a 200 Hz RBW, nothing seen. This with Ultra enabled. Cheers, David -- SatSignal Software - Quality software for you Web: Email: davidtaylor@... BlueSky: @gm8arv.bsky.social, Twitter: @gm8arv
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I just received my ZS-407 from R&L Electronics. I do frequency coordination for large events and the most common frequency range for wireless devices is in the 470 MHz to 608 MHz UHF TV band. I set the ZS-407 for a start frequency of 470 MHz and a stop frequency of 608 MHz. The RBW was initially set for auto. With no antenna on the 407 it was just showing a noise floor that was around -90 dBm. When I changed the RBW to 100 kHz, it displayed a spurious signal around 533.8 MHz. As I drilled down into this signal and reduced the RBW even lower, it turned out to be two very narrow bandwidth spikes at 533.725 MHz and 533.775 MHz. My older TinySA Ultra with the exact same settings does not display these signals. I also tuned my Icom IC-R30 to those two frequencies in CW mode and confirmed that no signals were received. Can anyone else see these “birdies” on their ZS-407 or is it just mine?
- Otto
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Re: Measurement problems, strange step noise floor behavior between 600-800kHz
No need to feel embarrassed. ?The tinySA takes some time to get familiar with. ?We are all in this group to share and learn from each other. ?Have fun with your new device.
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Roger
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Re: Brand new to both TinySA AND Spectrum Analyzers
?"You should only engage the LNA when your other efforts to pull a signal out of the noise have failed..."
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You don't know what signals are there *unless* you try the LNA. You can always turn it off again. In any case if you use the MEASURE menu I believe the SA takes control of such things anyway...
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Re: Measurement problems, strange step noise floor behavior between 600-800kHz
Thank you so much! You are absolutely correct! Of course, the scope was still set to the 10x probe endorsing to increase sensitivity on the TinySA.
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I am totally embarrassed now and feel sorry to have wasted your time. After re-calibration all problems regarding my questions have resolved.
Nonetheless, I was able to hand-calibrate the TinySA with a -20dBm sensitivity difference across the entire range.
?
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Thank you again
Lutz
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On Tue, Jan 21, 2025 at 05:03 PM, <nighthawk.eng@...> wrote:
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Maybe grounding everything to the house earth could be a good or a terrible wrong idea?
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With things like that the only way to know is to try.? Some electronics instruments (my RF RMS voltmeter for one) and musical instrument amplifiers have a switch which allows floating or grounded use.?
A conductive tent or screened/shielded room will likely help and is unlikely to hurt.? Turn your cell phones off/keep them at a distance.
Best regards, Don?
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Bruce Akhurst
David J Taylor
Roger Need
Donald S Brant Jr