During the time, I have observed a smaller irritating thing - the surface temperature of the unit is too high after half an hour in receive mode.
For this reason, I will suggest a minor mod to the fan control circuit located at the PA board.
During receive mode the fan normally is switched off or is operational if the inside temperature is too high (fan control decision).
My suggestion is to supply the fan with a low voltage (app. 6 volt) during its off period.
OBS: The internal fan control will of course control the fan as before this modification.
Opening of the unit:
Remove 11 black screws from the top cover; 2 from the handle and 11 shining screws in the grey chassis cover; now you can locate the PA most left in the frame.
Power amplifier with fan control circuit which is located at the bottom left for center.
In the middle fan control
The only component for the modification, an 8V2/1.3W zener diode.
OBS: To day, I will use a 7V5/1,3W zener diode instead!
Fan control with the zener diode
Macro of the zener
Fan control schematic with my modification upper right.
Check circuit for possible short circuits and you are ready for testing the circuit. Switch on power and enjoy a silent fan and a mild breeze through the cabinet.
Switch off power to the unit!
1. Remount the grey chassis cover
2. Arrange the loudspeaker cable as earlier
3. Remount the top cover and handle.
How simple!
Good luck with the mod