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Malfunction

 

Initially, Tinysa passed the SelfTest and self-calibration tests, now, after a few hours of operation, it fails SelfTest number 10 and 14, and if I activate the LNA during the measurement it disconnects the input.
What could be wrong?
 

Make sure your battery is fully loaded
--
Designer of the tinySA
For more info go to

 

The problem remains even with 4.2V on the battery

On Sun, Aug 18, 2024 at 11:59?AM Erik Kaashoek via <erik=[email protected]> wrote:
Make sure your battery is fully loaded
--
Designer of the tinySA
For more info go to

 

Contact your seller
--
Designer of the tinySA
For more info go to

 

Remember, the first stage in any receiver system, that includes spectrum analyzers, is predominantly responsible for determining the noise performance of the entire receiving system.

An excellent tutorial addressing the noise figure / noise temperature of cascaded stages can be found at? (there is nothing but simple algebra, no calculus, required):

? ? ??

Dave - W?LEV


On Sun, Aug 18, 2024 at 5:37?PM Vasy Vasii via <nectariebeje20=[email protected]> wrote:
Why does the noise level decrease by 30 dBm in software with LNA, while BGA2817 only provides a 25 dBm gain??
I will attempt to replace the BGA2817 as it is inexpensive, at only $0.145. I suspect the issue is related to the LNA.



--
Dave - W?LEV
 

Why does the noise level decrease by 30 dBm in software with LNA, while BGA2817 only provides a 25 dBm gain??
I will attempt to replace the BGA2817 as it is inexpensive, at only $0.145. I suspect the issue is related to the LNA.
?
Can anyone with a working TinySA Ultra tell me what the calibrated signal level of a 10MHz signal is with a 3kHz SPAN, when received via cable, without a cable, and without a cable but with an LNA?
I'm getting -35.4dBm with a cable, -110dBm without a cable, and -135dBm without a cable but with an LNA.

Thanks a lot!
 

Are you referring to Cable TV??

Without the cable.....?? What are you using for an antenna on the SA and the spacing between the cable end and the SA antenna??

Please be more specific.

I don't have CATV, but do have a good signal generator.? If you refer to a sig. gen. what level is the sig. gen. output set to?

Dave - W?LEV


On Sun, Aug 18, 2024 at 5:59?PM Vasy Vasii via <nectariebeje20=[email protected]> wrote:
Why does the noise level decrease by 30 dBm in software with LNA, while BGA2817 only provides a 25 dBm gain??
I will attempt to replace the BGA2817 as it is inexpensive, at only $0.145. I suspect the issue is related to the LNA.
?
Can anyone with a working TinySA Ultra tell me what the calibrated signal level of a 10MHz signal is with a 3kHz SPAN, when received via cable, without a cable, and without a cable but with an LNA?
I'm getting -35.4dBm with a cable, -110dBm without a cable, and -135dBm without a cable but with an LNA.

Thanks a lot!



--
Dave - W?LEV
 

Using a TinySA SMA male cable to connect between the calibration (CAL) and radio frequency (RF) ports, with the 10MHz calibration signal enabled (from Mode)
 

 

On mine, after a calibrate 100kHz to 5.340Ghz and passing the entire self-test, Setting Calibration Output to 10 MHz. Measuring the 10MHz with 3kHz span, I'm getting -35.0dBm with CAL-RF jumper cable, -107.5 dBm without cable, and -130.3 dBm without cable and LNA on
?
Toni
 

setting the calibration output to 30 MHz. Measuring 30 MHz with a span of 3 kHz, I get exactly your values -35.4dBm with a cable, -110dBm without a cable, and -135dBm without a cable but with an LNA
 

On Sun, Aug 18, 2024 at 10:58 AM, Vasy Vasii wrote:
-110dBm without a cable, and -135dBm without a cable but with an LNA
This 25 dB difference, not 30
--
Designer of the tinySA
For more info go to

 

I can replace BGA2817 (25 dB gain) with BGA2818 (30 dB gain) ?
?
 

No
--
Designer of the tinySA
For more info go to

 

What is the value of capacitors C34 and C35 for TinySA Ultra?
Their capacity influences the LNA's self-excitation stability and, implicitly, reliability.
 

 

As I understand it, the tests are set to fail if the capacitors are not the exact value, causing certain components to burn while they are running.
 

The selftest can not test all frequency dependent aspects of the tinySA components.
Normally this is not needed as capacitors and inductors very rarely change values due to overloading.
The LNA will fail long before the capacitors around it may fail and this will be detected in the selftest.
Missing or incorrectly soldered capacitors around the LNA will be detected in the selftest
--
Designer of the tinySA
For more info go to

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