Premise: I had a Baofeng GT-3 TP Mark III 8W stored and never used, this morning my nephew has found It and He tried to "play with It" transmitting at maximum power(8 Watt) despite antenna wasn't attached, (seems He has transmitted for several minutes).
Now I have tried the radio in a near range indoor transmission and in channel mode apparently seems working, but in frequency mode It activates on all frequencies, as there is an incoming transmission, but It receives noise on all frequencies even at maximum squelch level (9).
Since I haven't tried this radio before, I don't know if this depends on local radio pollution and bad factory squelch parameters, that eventually I can adjust with CHIRP(you can see the current parameters in the image), or this could be caused by some noise filtering component that has been burned during the transmission without antenna making It more sensitive to any radio disturbance.
How could I determine the possible damages of transmission with detached antenna in portable ham radios? (consider that I haven't any special testing equipment)
What are the kinds of damages that could occur?
In case the damage occur, is It something of the kind radio totally stop to receive and transmit or could happens even kinds of damages that make the radio performing worse?
Thanks to everyone help me.