When my power dropped from 5w to 2w I tacked wires onto the drive side of T501 (actually used D503 and D504 empty holes).? Then you can monitor on a scope if the Q503-Q506 are OK.? In my case I saw a lower signal on one pair that was called by a failed BS170.?
Note in my case at turn on until the first transmit there was high supply current because the current firmware does not shut down the PA drive through Q507 until after a first transmit.? So if you see a high initial current that drops after a transmit cycle it points to a PA (BS170) issue
