Spectrum analyzer, keys _3 / 9

[pietss]

Spectrum analyzer, keys 3 / 9 - increases/decreases maximum dB value (vertical scale) , approximately what is the average value to enter?

edit.
Button functions:
LNAs - Short Low Noise Amplifier
LNA - Low Noise Amplifier
PGA - Programmable Gain Amplifier
IF - Intermediate Frequency
I only partially understand the meaning of these settings. If anyone can briefly explain to me when it is appropriate to vary the values ​​depending on the case, I would thank them.

Thanks

[pietss]

If you're interested, regarding the settings keys 3 / 9, you can read here https://alfaexploit.com/en/posts/hamradio3/#spectrum-analyzer
As for the other settings LNAs LNA PGA IF in this radio, they are extremely technical and for those without the skills they are partially understandable, however if practical examples were used probably many more people could understand what it is.
I found some more information elsewhere but not enough yet, I'll try to do more research.
Greetings