Is it possible to remove linking for player's spawn chunk to start radar building? I mean that mod try to calculate the first placing radar from chunk, where player spawn. Instead, first radar not needed to help, and others must be calculated from first's position.

I am not sure if I understand your question exactly, especially on what "linking" means.
My tutorial on information page first have the radar ALREADY in place, then player stands in the same chunk, and uses the information panel to calibrate the settings.
This mod, if using correctly, helps placing the follow-up radars, NOT helping nor limiting the first radar.
Honestly, I don't see why you think it was forcing you where to place your first radar...

About "player's spawn chunk"... Every coordinate system needs an origin (0,0), right? Factorio internal API position needs an origin, by default using spawn position as origin. It is natural for this mod to use this as origin too.

sorry for long delay and thanks for response)
but i mean is it possible to "save" (or get this info in another way, if it possible) the first radar position? and then use save data, instead of setting offset in mod settings.
example: i set first radar, set setting for offset, but then i can change position of first radar and must change settings for offset too, this is not really user-friendly behavior, IMHO

I am still not sure what exact questions you are having or what problems you are facing. I try to understand what you mean from your text, and try to answer that...

Inputting offset values in mod settings is more-or-less saving the position of the first radar, except that they are two simpler single-digit integers calculated as chunk coordinates (instead of the exact multiple-digit position coordinates). There are no real differences between "save data" and "offset values" as mentioned in your statement.
Or are you more satisfied/confident by having to type large values of position coordinates instead?

For vast majority of users, there is no need to move the first radar. "First" radar is not meant to be moved at all. If it gets eaten by biters, placing a new one on top of that absolutely does NOT require any recalibration! Radars placed later or elsewhere also do not require any calibrations. Calibration only needs to be done once per map. I do not see how this SINGLE calibration is not user-friendly, assuming it is done correctly.

If you really need to change position of the "first" radar, of course you have to recalibrate as well.
But then my question is WHY you have to move your "first" radar? What is your use case?
Are you playing some special scenarios with special scripts to move your buildings quite often?