NASA/M Tech SX 35 radio speaker output

[Plevier]

I know this is a bottom of market unit but I'm finding it perfectly OK except for one annoyance - when you plug in an external speaker it cuts off the internal one. So only the helm or the navigator can hear, not both at once!
Looking inside, the audio output is one that would easily drive 2 speakers and it's on a heat sink. However I can't get to the connections on the ext spkr socket to bridge the cutout without removing the main PCB which means disturbing RF connections - not a good idea. (The socket is board mounted not on flying wires.)
Has anyone out there overcome this, or does anyone have a PCB layout & cct that would let me work out if I can connect somewhere on the top of the board please?
Thanks
Mike

 

[fireball]

put a second external speaker inside ...

 

[waterbuffalo]

I have installed a small speaker at the chart table as well as the cockpit speaker.

Using just the external o/p from the radio and a 3 way switch I can switch between using the small chart table speaker or the cockpit speaker, or both speakers together.

This means that the built in speaker is not used at all.

 

[Playtime]

Or, slightly simpler, connect the external (cockpit) speaker via a simple on/off switch. That way the internal speaker (a separate small speaker mounted at the chart table) is always on and the external speaker can be switched on/off as required.

I have the same radio and it works for me!