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Which adf4350?

Above 1GHz RF is like water. It flows? through every hole
Hiding with the spur removal does not work as the spur removal removes spurs that do not actually exist but this 48MHz harmonic leakage is an actual signal.
In a next HW revision (not planned) I will pay some extra attention to them.

The TinySA doesn't use the ADF4350, it uses a couple of Si4432's.

Regarding ADF4351, would the Tninsa perform better with these rather than adf4350?

Steve L ? G7PSZ

Now the 64,000 dollar question.

What could be done to suppress them?

Either hide them with software tricks, such as the spur-removal option, but that might leave “holes” in the spectrum, or additional filtering/ decoupling/ screening on the board, which is out of the question for most current owners.

There is of course the human software modification - learn to live with it and adjust practice accordingly.

Out of interest, I was playing with my nanoV2 to improve screening. I found that things seemed to be worse if I applied conductive (absorption) tape inside the case and even laying the device (in FR4 unclad case) on a flat metal sheet also made things worse, especially above 2.5ghz.

Steve L. G7PSZ

Yes the unit certainly has limitations, though for the price is not to bad really.

Here's a -4dBm carrier from an ADF4351 at 50MHz.

The TinySA shows a wide flat top and noise floor of only 45dB down at 12kHz away from center, where as in actual fact the carrier's noise floor is 80dB down by the time your only 1kHz away from center.

A useful unit all the same.

On Mon, Aug 17, 2020 at 06:00 AM, hwalker wrote:

Your explanation and an illustrative screen shot deserve a Wiki entry, possibly under 'Limitations' or as an addition to the FAQ topic, "Question:?Even without anything connected I still see some signals ".

Done,
The 4.8MHz is indeed present.

On Mon, Aug 17, 2020 at 03:16 AM, Erik Kaashoek wrote:

These are 48MHz harmonics generated by the MCU. For now all tinySA will show them at 48, 96, 144, 192 and 240 MHz

Erik,
? ?On my tinySA there also appears to be a sub-harmonic of the 48MHz clk at 4.8MHz.? Possibly a divide by 10 output?

LOW and HIGH INPUTS terminated in 50ohm loads.


Your explanation and an illustrative screen shot deserve a Wiki entry, possibly under 'Limitations' or as an addition to the FAQ topic, "Question:?Even without anything connected I still see some signals ".Perspective buyers should know what to expect if the internally generated MCU signals will be an issue to them.- Herb

These are 48MHz harmonics generated by the MCU. For now all tinySA will show them at 48, 96, 144, 192 and 240 MHz

Have I just been unlucky and got a bad unit, or does everyone suffer spurious signals on their TinySA?

I see specific signals at 144.20MHz, 192.15MHz, and 240.19MHz.

They are unstable, and wander over a few hundred kHz, during a period of about an hour. Each are 12-15dB above noise floor in 10kHz RBW.

They are definitely internally generated. I have applied 50Ohm loads to the SMA connectors, and even operated the device inside a Faraday cage, but still the spurious signals remain visible.

Any feedback welcome.

John

Yes, to be done

Very good.

Could the firmware not have used the unique CPU serial number to create the device ID ?

On Sun, Aug 16, 2020 at 08:33 AM, ajparent1/kb1gmx wrote:

I've already used mine for tracking power line noise t 300mhz using a
small yagi for that band.

With an untuned amplified .3M untuned HF loop I"ve tracked all sorts
of items emitting significant noise.

You can measure the field strength of a source in dBuV/m if you change display units to dBuV and use a transducer calibrated in dB/m.? At a single frequency you can enter the tranducer factor (plus pre-amplifier gain if used) in Level->External Amp for a direct reading of field strength (only accurate at 1mtr distance from the source).

Similar technique using a current probe can be made for dBuA measurements.

- Herb

The tinySA uses the same VID/PID as the NanoVNA so if you are writing a script or program to communicate with the tinySA, and both a NanoVNA and tinySA are connected to your computer at the same time, you need to perform extra steps to automatically identify which port the tinySA is connected to.

1. The most reliable way is to query a connected port using the 'info' console command.

? ? >info

?

tinySA v0.3

2019-2020 Copyright @Erik Kaashoek

2016-2020 Copyright @edy555

SW licensed under GPL. See: https://github.com/erikkaashoek/tinySA

Version: tinySA_v1.0-49-ga63df47

Build Time: Aug 4 2020 - 17:52:05

Kernel: 4.0.0

Compiler: GCC 7.2.1 20170904 (release) [ARM/embedded-7-branch revision 255204]

Architecture: ARMv6-M Core Variant: Cortex-M0

Port Info: Preemption through NMI

Platform: STM32F072xB Entry Level Medium Density devices

If? 'tinySA' is contained in the response you have found the serial port the tinySA is connected to.

2. If you happen to have two tinySA's connected to the same computer, perhaps for automated frequency response measurements, then I've found the best way to? uniquely identify each tinySA is by using the 'deviceid' command.? Each tinySA is serialized at the factory with an 8-digit serial number.? The serial number is not written in the tinySA firmware, but Erik has included a 'deviceid ' console command that allows the user to set and query a deviceid.? If no deviceid has been set, or after a 'clearconfig 1234' console command, then querying the deviceid returns the following:

?> deviceid
? returns 0000

I always set my deviceid to my factory serial number (20070007):

?> deviceid 2007007
?> saveconfig 1234
?> deviceid
? returns 20007007

Always perform a 'saveconfig 1234' after setting a deviceid so that the id will be retained in flash memory.? Now your program or script can uniquely identify which tinySA is connected to a port by querying its deviceid number.? This works well, but only if the user has assigned a unique deviceid to each tinySA.

- Herb

I've already used mine for tracking power line noise t 300mhz using a
small yagi for that band.

With an untuned amplified .3M untuned HF loop I"ve tracked all sorts
of items emitting significant noise.

Very handy.

Allison
-----------------------------------------
Please post here, direct emails go to a dead letter box.

On Sat, Aug 15, 2020 at 11:09 PM, Erik Kaashoek wrote:

On Sat, Aug 15, 2020 at 03:30 PM, OneOfEleven wrote:

, I already started writing PC software for it.

Make sure you use the "scanraw" command i.s.o scan or sweep as scanraw can do unlimited points and sends data in binary, much faster

? ?Besides the faster speed and unlimited points, the tinySA 'scanraw ' command transfers corrected data - unlike the similar command on the NanoVNA which transfers raw data and requires you to externally apply calibration factors.? That's the major reason I've never used the 'scanraw' command on the NanoVNA.

? The binary format of the data returned by the tinySA 'scanraw' command is easy for C programmers to convert to actual dBm values.? Programmers using higher level languages like Python, will struggle doing the conversion until some examples start appearing on the web.

? From notes provided to me from Erik:

? ? ?Scanraw command outputs: ? ? ? ? ?byte end: '}

? ? ? ? ?level in dBm? = ((byte3 + (byte4) * 256) )? / 32 - 128

? - Herb

Don't forget to check PC supplies, The worst I found was a PICO supply.?

A very useful use of the TinySA is to track down sources of interference.

The horrors of today's unfiltered unscreened (and often unsafe - we had one leave burn marks all up our lounge wall after it exploded) chinese switched mode regulators/supplies, they have literally destroyed today's HF (and now slowly moving up into VHF/UHF) communications for many people around the globe :(

This is just one example - a baofeng walkie-talkie charger.

On Sat, Aug 15, 2020 at 03:30 PM, OneOfEleven wrote:

, I already started writing PC software for it.

Make sure you use the "scanraw" command i.s.o scan or sweep as scanraw can do unlimited points and sends data in binary, much faster

On Sat, Aug 15, 2020 at 07:06 PM, hwalker wrote:

Is that the only change in FW release v1.0-52?

I think so.