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And then it occurred to me I can do the same trigger trick to pause a sweep once a signal above trigger level has been seen so here is the frequency scan of the 433MHz RF remote control.



Not so clean but the at least we know the frequency of the transmission (433.8MHz)

A rather basic trigger mechanism is implemented,
If a signal is above a settable level a capture is done.
Here a 433MHz RF remote control transmission



I need to add some info on the horizontal time scale and decide if it is going to be trigger once or trigger always as now you have to pause sweep to prevent further captures

Erik,
? ? Can a tracking generator be created using an external mixer and LPF driven by the tinySA LO?? I have a WJ 0.2-500MHz mixer and 300MHz LPF?on hand. I'm not clear what I.F.? is normally used to drive the mixer, and whether a preamplifier is necessary after the LPF.?

? ? Just wondering if a set-up like that would be an alternative to purchasing two tinySA's to enable the tracking option.??

- Herb

On Fri, May 15, 2020 at 12:09 AM, <erik@...> wrote:

The VID/PID are identical to the nanoVNA (for now)
The virtual serial port (when using it with windows) becomes? a COM port so no need for VID/PID there

The info command output starts with "tinySA" with version info added (currently v0.2), rest is similar to nanoVNA

Erik,
? ?Thanks for the replies.? When I have more than one serial device connected, the VID/PID helps my scripts automatically identify the device I want to communicate with.? The "tinySA" in the "info" command output will let my scripts differentiate the tinySA from a NanoVNA.

? One more request.? When you get the time could you post what the "help" console command returns?? I'm interested in seeing the commands available for use with the tinySA.

- Herb

Herb

The VID/PID are identical to the nanoVNA (for now)
The virtual serial port (when using it with windows) becomes? a COM port so no need for VID/PID there

The info command output starts with "tinySA" with version info added (currently v0.2), rest is similar to nanoVNA
?Thanks for proofreading the wiki (and the kind words)
I have difficulty to spot these errors.

On Thu, May 14, 2020 at 07:01 AM, <erik@...> wrote:

Both ports are AC with multilayer SMD capacitors. I guess up to 25 Volt should not be a problem.
Let me check when I'm back to where the documentation is.

==========================================================
Erik,
? ?While you are checking the documentation for the dc rating of the tinySA's? input ports, could you also see what the? VID/PID's are for the virtual serialport?? They are not identified in your online documentation or in the tinySA NanoVNA-Saver branch.? Also, what does the "info" console command return for the tinySA?

? I can see you put a lot of attention into the Wiki page.? Impressive one man effort on your part with the Wiki, software and hardware.? On the Wiki Frequency Menu page I noticed START notated twice:

• START?sets the scanning to start/stop mode and sets the start frequency
• START?sets the scanning to center/span mode and sets the frequency span

? Looks like the second entry should be SPAN.

- Herb

Both ports are AC with multilayer SMD capacitors. I guess up to 25 Volt should not be a problem.
Let me check when I'm back to where the documentation is.

Erik,
? ?You've already noted the input ports are limited to +10dBm max.? What is the DC limit of the input ports?? I assume the limit is de-rated to half the dc rating of the input port coupling capacitors, whatever that value is.

- Herb

Sala,
I have an SDRPlay RSP2 that I have used as a spectrum analyzer with the RSP-Spectrum-Analyzer software.? ?I would say that it is good for checks below 40 MHz, so good for tight in spurs detection, and OK for harmonics up to 40 meters (I have not tested 30 meters, as no interest there).? When testing for 20-meter harmonics, I am getting a spur around 53 MHz that may be related to the USB clock.? The one thing that I do use it for that seems to work well is two-tone testing.? The RBW seems to be small enough to see both of the tones.

I have ordered the RSP1A to see if that unit has a better response above 40 MHz.? It also has a 14 bit DAC, as opposed to the 12 bit in the RSP2.

The above are my opinions based on my experiences so far.? Yours may be different.
73
Evan
AC9TU

The cheap msi.sdr rsp1 clone is not good.

These are definitely interesting and the price is not overly high.
Are SDRplay models good as general spectrum analyzers, Are there a lot of ghost lines and so on.

Tiny Sa and a SDR are good pair.
I think checking modulation close to carrier and checking spurs and harmonics are two different things. It is not IMO necessary to do both at same sweep.

That is the same? as what I see with my MSI.SDR SPR1 clone. But is soon as you apply an input signal the spurs start to explode

I have been experimenting with an MSi.SDR RSP1 clone from China for a short while and must admit I have only used it for relatively narrow span measurements. IMHO the RSP SA software has many nice features and is slick to use.

Attached is what the baseline looks like with a 1GHz span with no signal and terminated input and RBW of 500Hz. I have not done any calibration to match the software to this particular receiver. However this should illustrate the internal spurs without any signal input for this particular RSP1 clone.

It appears some switching takes place around 60 MHz and possibly a pre-amplifier is inserted at 420 MHz. I had the clock spur removal feature turned on which removed many spurs. There are significant spurs around 196 MHz and 401 MHz plus a few other low level spurs.

I suspect this software would work better with a genuine RSP1A that has more filtering. Unfortunately I don't have an RSP1A to make a comparison.?
?

I tried a cheap RSP1 Chinese clone with the RSP SA PC software.
It works very well for small RBW but when doing wider sweeps I saw many spurs and I was never sure if they where really there or where internally generated.
Is there in this group someone with experience with an RSP1?

Greetings,

? ? ? ? ? ? IMHO the major advantages offered by the tinyVNA concept are handheld portability and cost. The instrument concept is ideal for many portable field measurement needs. Professional field portable, battery powered spectrum analyzers are typically ten to a hundred times more expensive - well beyond the budget limitations of the majority of hobbyists.

? ? ? ? ? Usually the measurement of modulation components can be done conveniently?without the need for handheld portability. With modern day DSP technology using computer muscle power all that is needed for the measurement of modulation components is an inexpensive SDR receiver along with a PC running freeware such as HDSDR. A nice, quite low cost combination is SDRPlay's RSP1A receiver running under their free accessory RSP Spectrum Analyser PC software. That combination offers spectrum analysis that has a professional feel to it with frequency coverage from VLF to UHF. With the selection of a 20KHz span the RSP SA resolution bandwidth can be reduced to less than 1 Hz.

? ? ? ? ?But the relative downside of using an SDR receiver as an analyzer is that it needs to be tethered to a PC thus it does not offer a nearly as portable a concept as the tinySA. The tinySA appears to provide sufficiently narrow resolution bandwidth capability to separate most signals which IMHO should make it a good fit for many uses other than modulation component analysis.

Tom, VA7TA

That will take a bit of time to configure my linux system for that.

I started with installed version to get a handle on "normal" operation.
Doesn't have to work perfect that way only to get a feel.

Allison
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Yes.
Please make sure you install the new FW as indicated on the wiki
You can choose to use ch.dfu or ch.bin or ch.hex

Received mine today and installed a 450mah lithium battery for?
familiarization and testing.

Quick question is the using set up to charge the battery from a USB source?

Allison
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Have a look at this post where I show the side band suppression measurement using a softrock RXTX and a tinySA

/g/HBTE/message/1126