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Erik,
? A question came up while I was demonstrating the tinySA to some club members.

? The tracking marker is supposed to track the peak of the displayed signal but, as shown in the following screen shot, that is not always the case.? The screen shot is the tinySA 30MHz calibration output at 100kHz span. The manually placed marker 2 is 1.5dB higher than the tracking marker 1. Also, a max-left or max-right moves either marker to -26.3dBm instead of -24.8dBm.



- Herb

On Sat, Aug 22, 2020 at 06:21 AM, hwalker wrote:

The tracking marker is supposed to track the peak of the displayed signal but, as shown in the following screen shot, that is not always the case.?

I added some explanation to the wiki:?
In short. If no maximum (at least NOISE LEVEL above the surrounding minima) is found the tracking marker is positioned at the start of the trace.

On Sat, Aug 22, 2020 at 06:31 AM, Erik Kaashoek wrote:

On Sat, Aug 22, 2020 at 06:21 AM, hwalker wrote:

The tracking marker is supposed to track the peak of the displayed signal but, as shown in the following screen shot, that is not always the case.?

I added some explanation to the wiki:?
In short. If no maximum (at least NOISE LEVEL above the surrounding minima) is found the tracking marker is positioned at the start of the trace.

? ?Thanks for the explanation.? I'll add it to my notes.? It also explains why max->right search places the marker at the end of the trace.?

? ? My only comment is that the behavior makes sense for a tracking marker but a normal marker should just go to the maximum displayed level, or the first one found searching left to right if there are multiple display points of equal maximum value.? That is how the max or peak function works on other spectrum analyzers I have used.
? ?
? ?Any chance of adding a marker->search->peak? button that functions the same way?

- Herb

So in MARKER/MARKER SEARCH/ add an option GLOBAL MAXIMUM?
If you do a marker search on a tracking marker it automatically becomes a normal marker. Is that behavior OK?

Forgot to ask.
The zero Hz peak can not be ignored in a GLOBAL MAXIMUM search as it is unclear how far to ignore (starting from 0Hz). OK?

On Sat, Aug 22, 2020 at 08:09 AM, Erik Kaashoek wrote:

1. So in MARKER/MARKER SEARCH/ add an option GLOBAL MAXIMUM?
? ?[A more conventional term would be MARKER PEAK?but, as Kurt once said, the tinySA has options sometimes not available on a conventional spectrum analyzer and therefore, can use its own naming conventions.]

2. If you do a marker search on a tracking marker it automatically becomes a normal marker. Is that behavior OK?
? ?[I don't usually do a search on a tracking marker because it will override the search and jump back to tracking - except when the display is paused.? Its logical that if a user does a search using a tracking marker that they probably no longer want tracking behavior to apply, so I would agree with you that switching to normal marker mode is the correct behavior.]

Forgot to ask

3. The zero Hz peak can not be ignored in a GLOBAL MAXIMUM search as it is unclear how far to ignore (starting from 0Hz). OK?
? ? [Yes.? The user will learn soon enough that any measurements with the zero peak visible will affect measurements like marker peak?and that the tinySA settings need to be changed to minimize its impact.? This is not only true with the tinySA but Agilent and R&S spectrum analyzers that I have used.]

4. So in MARKER/MARKER SEARCH/ add an option GLOBAL MAXIMUM???
? ?[My preferred option name would be MARKER PEAK?but most of the other menu names you have chosen have grown on me.? For me its more the added functionality than anything else.? Also, if you do manage to add this menu item to a future update, then adding a corresponding??marker x peak?(sends marker x to the display peak value and returns the value and frequency) to the console command list would be helpful.]

Thanks for considering.

- Herb