I just got my new 3 channel TQi radio with docking station, first thing I did like nearly everything I have is dismantle it and see whats new.
Inside I find a spot on the main board clearly intended for use with the 4/5 channel switch.

Attaching a switch doesn't do anything, and unfortunately there's no 'VCC' port to earth and see if anything happens from there, also tried resetting the unit and having a general poke around of the pins, some turning the unit of and on again, but with no change to settings.

So far I've fount the thumb switch is three position capable, possibly analogue I'll confirm at a later point.

Just wondering if anyone else is on the case to unlock extra channels?