Back in the early '50s the French Foreign Legion was fighting in what
was then known as Indo-China. They had network that used callsigns
starting with TTx - some I can recall are TTA, TTN, And TTV, but
memory has faded as to relating a location to call sign.

Does anyone have older call sign lists that might help with this?

The control station was FLZ and the network used CW, if that helps?

Thanks,