Thanks for the link Fish. Not sure I want to go back to 8km, and the links for Alert Sonarman 16km are dead.
I guess it is time to download TT tweaks and mod my own sensors.dat. Rubini stated that it was just a couple of tweaks in the hydrophone section and was identical to the 8km version.
If I compare his modded sensor.dat with mine, it shouldn't be too hard to figure out what changes are required.
Unless someone has still has a 4 year old mod zipped on their hard drive they'd be willing to email...