Re: Noise figure measurment not built into standard (2.8") TinySA?
The Ultra has a built-in LNA which is needed to measure the NF of a amplifier.
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Here a video that demonstrates how to do a NF measurement using the tinySA Basic. FOr this you need a extra LNA.
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For the tinySA Ultra you can do it as shown here:
No extra LNA is needed.
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Designer of the tinySA
For more info go to
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Noise figure measurment not built into standard (2.8") TinySA?
I have both the standard and Ultra versions of the TinySA.? Both incredibly useful tools.? I recently became aware that the Ultra has built in ability for noise figure measurements on LNAs.? Purely out of curiosity I am wondering why this measurement is not possible with the standard TinySA...i.e. is there something intrinsic in the design that makes it impossible?
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I am also wondering if there are any "tricks" to making a NF measurement with a standard TinySA....i.e. would I have to have a calibrated noise source etc?
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Not to mention 1 port handles it's whole frequency range... Get an ultra?!
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The Ultra is much better for doing Bessel nulling, its resolution bandwidth is much narrower.
Gary
W9TD
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First of all I must explain that I am pretty much a newbie when it comes to spectrum analyzers and I apologize if the answer to my question should be obvious.
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I have a TinySA and I've been working on an amateur DMR repeater that is using a Repeater Builder STM32-DVM controller. It became necessary for me to null out the FM carrier and the Bessel null procedure was recommended. However, I wasn't able to properly discern any carrier level changes when adjusting the Tx on the controller. To my understanding, the High channel input does not have enough resolution but the Low channel input does. All the examples of using a TinySA that I can find seem to be performed on a VHF or lower frequency.
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My question is this, would a TinySA Ultra+ model work in this situation? If so, any help with setup recommendations would be greatly appreciated.
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Regards and thanks in advance,
Chris
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my headphone jack came off!
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I am starting this new thread because the old thread below is locked:
/g/tinysa/topic/possible_design_issue_with/109589683
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Yesterday, the earphone jack on my 2-year old TinySA detached from the PCB. The jack's footprint has three pads, two of which are connected by a very fine trace (fig. 1) and one of the two connected pads is missing.
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I did not attempt to join back the missing pad because soldering a fine wire on the broken trace is beyond my dexterity. Fortunately, the jack's 3 solder terminals are replicated on the top of its body (fig 2). So, I replicated the missing connection by soldering a fine wire between the 2 top terminals.?
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Then I soldered back the other two terminals to their respective PCB pads. I would prefer to mechanically secure the jack by tying it down to the PCB using either cable tie or twisted wire, but cannot do so because the LCD on the opposite side prevents me from drilling holes (fig. 3).
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So, I ended up slathering epoxy glue on the jack and PCB (fig. 4).
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To prevent the jury rigged jack from detaching again in the future, I resort to permanently leave a pigtail connected to it (fig. 5).
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Feedback welcome!
73, Leong, 9M2LCL, ex-9W2LC.
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Locked
Re: OFF topic thread re: member's age SORRY
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Locked
Re: OFF topic thread re: member's age SORRY
No, 82 is not "old".? 82 is "wise".
Dave - W?LEV
ALL,
I'm GUILTY of continuing an OFF topic thread.? Sorry.? Is 82 old
or .........?
Remain WELL & be SAFE!
Robin
- - - - - - - - - - - - - - - - - - - - -
On 3/6/2025 10:21 AM, Mike C. wrote:
Gotcha ya beat, Dave, I was born the day before Ruzevult DIED.
So that puts me up on the stack.
Mike C. Sand Mtn GA
On 3/5/2025 11:12 AM, W0LEV via
wrote:
Welcome to the elete "Old
Fossil Club", Dan.? I'm 78.25 years "wise".?
Dave - W?LEV
On Wed, Mar 5, 2025 at
12:39?PM Dan Heather via <jdanheather= [email protected]>
wrote:
at 77.5 years, I learn something new everyday!? But
this topic makes my head hurt (in a good way)!? Thanks
folks!
--
--
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Locked
OFF topic thread re: member's age SORRY
ALL,
I'm GUILTY of continuing an OFF topic thread.? Sorry.? Is 82 old
or .........?
Remain WELL & be SAFE!
Robin
- - - - - - - - - - - - - - - - - - - - -
On 3/6/2025 10:21 AM, Mike C. wrote:
toggle quoted message
Show quoted text
Gotcha ya beat, Dave, I was born the day before Ruzevult DIED.
So that puts me up on the stack.
Mike C. Sand Mtn GA
On 3/5/2025 11:12 AM, W0LEV via
groups.io wrote:
Welcome to the elete "Old
Fossil Club", Dan.? I'm 78.25 years "wise".?
Dave - W?LEV
On Wed, Mar 5, 2025 at
12:39?PM Dan Heather via <jdanheather= [email protected]>
wrote:
at 77.5 years, I learn something new everyday!? But
this topic makes my head hurt (in a good way)!? Thanks
folks!
--
--
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Re: How to apply frequency-dependent Antenna Factor
Gotcha ya beat, Dave, I was born the day before Ruzevult DIED. So
that puts me up on the stack.
Mike C. Sand Mtn GA
On 3/5/2025 11:12 AM, W0LEV via
groups.io wrote:
toggle quoted message
Show quoted text
Welcome to the elete "Old
Fossil Club", Dan.? I'm 78.25 years "wise".?
Dave - W?LEV
On Wed, Mar 5, 2025 at
12:39?PM Dan Heather via <jdanheather= [email protected]>
wrote:
at 77.5 years, I learn something new everyday!? But this
topic makes my head hurt (in a good way)!? Thanks folks!
--
--
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Re: How to apply frequency-dependent Antenna Factor
Yes, you could so long as you are at or below -30 dBm on the TinySA (I believe the spec is -26 dBm).? Add 107 you dBm to get dBuV.? Or more rigorously:
? ?? dBV = dBm + 10 lob[Z]?+ 90 ?
HOWEVER, the reg. testing requires you to search vertically in both vertical and horizontal polarizations for the maximum of at least 6 of the highest "quick-look" frequencies.? The "quick-0look" search should include measuring in both vertical and horizontal poilarizatioins at every 22.5-degrees of rotation of the DUT.
In addition, a good conductive "ground plane" (and it REALLY IS a GROUND PLANE - REFLECTIVE)? be present totally between the DUT and the antenna.? Without that, you can not make good regulatory judgement in a pre-compliance setup.
Dave - W?LEV?
Just a matter of spectral interpretation: Some time ago, I recognized that tinySA ultra offers a quasi peak display. But what I saw was something like attack and decay effects so to say over the time axis, or said in another way: along the frequency axis. But that's not quasi peak of a single frequency that's staying - let's say one second before the next frequency is swept up. But perhaps you'd get a reasonable result when the sweep is done as slowly as in standard tests.
Rob
On Tue, 04 Mar 2025 14:51:16 +0100, Magne Lauritzen via <mag.lauritzen= [email protected]> wrote: Good day,
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I would like to know whether I can apply the Antenna Factor (AF) for my calibrated biconical antenna to measurements being made by the TinySA Ultra. Antenna theory refresher: The AF is a value that lets you go from measured intensity to actual E-field intensity. It is critical when doing compliance testing of radiated emissions.
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If the AF was just a single value I could apply it to the TinySA settings as a pretend attenuator between the antenna and the TinySA. But the AF of my antenna is highly frequency-dependent, varying by over 20dB over my frequency range of interest.?
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Re: How to apply frequency-dependent Antenna Factor
Just a matter of spectral interpretation: Some time ago, I recognized that tinySA ultra offers a quasi peak display. But what I saw was something like attack and decay effects so to say over the time axis, or said in another way: along the frequency axis. But that's not quasi peak of a single frequency that's staying - let's say one second before the next frequency is swept up. But perhaps you'd get a reasonable result when the sweep is done as slowly as in standard tests.
Rob
On Tue, 04 Mar 2025 14:51:16 +0100, Magne Lauritzen via groups.io <mag.lauritzen@...> wrote:
Good day,
?
I would like to know whether I can apply the Antenna Factor (AF) for my calibrated biconical antenna to measurements being made by the TinySA Ultra. Antenna theory refresher: The AF is a value that lets you go from measured intensity to actual E-field intensity. It is critical when doing compliance testing of radiated emissions.
?
If the AF was just a single value I could apply it to the TinySA settings as a pretend attenuator between the antenna and the TinySA. But the AF of my antenna is highly frequency-dependent, varying by over 20dB over my frequency range of interest.?
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Re: How to apply frequency-dependent Antenna Factor
Welcome to the elete "Old Fossil Club", Dan.? I'm 78.25 years "wise".?
Dave - W?LEV
On Wed, Mar 5, 2025 at 12:39?PM Dan Heather via <jdanheather= [email protected]> wrote: at 77.5 years, I learn something new everyday!? But this topic makes my head hurt (in a good way)!? Thanks folks!
--
|
Re: How to apply frequency-dependent Antenna Factor
at 77.5 years, I learn something new everyday!? But this topic makes my head hurt (in a good way)!? Thanks folks!
--
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The same thing happened to me. In /AppData/Local/QtTinySA I deleted the QtTSAPrefs.db file and in its place I copied the QtTSAPrefs.db that comes in the .zip
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Thanks. That worked.
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Re: How to apply frequency-dependent Antenna Factor
Once you have worked out how to do it and have some measurements it would be nice if you could share some experiences as this is for sure a more advanced topic for many users
--
Designer of the tinySA
For more info go to
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Re: How to apply frequency-dependent Antenna Factor
That's great to hear. The application of AF was the only outstanding uncertainty I had about the TinySA before I buy it.
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Re: How to apply frequency-dependent Antenna Factor
You can enter the AFs and readings from the SA into separate columns within EXCEL and let that app do the arithmetic in a third column.? In addition, you could have EXCEL plot that corrected data with radiated emission limit lines.?
Dave - W?LEV
On Tue, Mar 4, 2025 at 06:33 AM, Magne Lauritzen wrote:
Thank you for the suggestion. Is the trace limited to 8 points linearly interpolated?
Yes
This may work fine in a pinch, but ideally I someone upload the full table of AF measurements (there's about 120). Could this full table be put on the SD card and subtracted from measurements?
Yes, Suggest to measure the exact frequency range of the antenna and store the trace on the SD, move it to a computer and edit the 450 values to reflect the antenna, move back to tinySA and load the trace from SD and subtract from active trace
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--
Designer of the tinySA
For more info go to
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Re: How to apply frequency-dependent Antenna Factor
On Tue, Mar 4, 2025 at 06:33 AM, Magne Lauritzen wrote:
Thank you for the suggestion. Is the trace limited to 8 points linearly interpolated?
Yes
This may work fine in a pinch, but ideally I someone upload the full table of AF measurements (there's about 120). Could this full table be put on the SD card and subtracted from measurements?
Yes, Suggest to measure the exact frequency range of the antenna and store the trace on the SD, move it to a computer and edit the 450 values to reflect the antenna, move back to tinySA and load the trace from SD and subtract from active trace
?
--
Designer of the tinySA
For more info go to
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Re: How to apply frequency-dependent Antenna Factor
Hi Erik,
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Thank you for the suggestion. Is the trace limited to 8 points linearly interpolated? This may work fine in a pinch, but ideally I someone upload the full table of AF measurements (there's about 120). Could this full table be put on the SD card and subtracted from measurements?
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Gary W9TD
Chris Groman
W5CDT
Mike C.
Dan Heather
Ken
Magne Lauritzen