Working with 4 Function Cabs With a 4-function cab (actually in most cases, five functions - F0 plus F1-F4), you will have to give something up! By using Tsunami’s automatic sound controls, hopefully it doesn’t need to be much.
Example 4: In this example, we will use automatic control for the Short Whistle, Mute, Injector, Brake Squeal, and Steam Release. FX5 and FX6 will be ganged up with F0 as was done for the 8-Function Cab example. F1 and F2 will continue to be used for the Bell and Whistle.
This frees up F3, which we can assign to the water stop, and F4, which we can use to control the dimmer. The only effect we must completely give up under this scenario is the coupler sound since it only maps to F10 -F12 (or F6-F8 with Function Swapping turned on). Sorry.
Using Table F, we can proceed to re-map functions as follows. Starting with F0, configure the forward direction to control the Headlight, FX5, FX6 and Dynamo:
Set CV 33 = 1 + 16 + 32 + 64 = 113
For the reverse direction, set F0 to control the Backup light, FX5, FX6 and Dynamo:
Set CV 34 = 2 + 16 + 32 + 64 = 114
Then configure F3 to control the Water Stop Sound:
Set CV 37 = 64
Set F4 to control the dimmer function:
Set CV 38 = 128.
To activate the automatic whistle signal, brake squeal and steam release, program CV 198 to 26. To activate auto-mute, program CV 113 to 120 which will shut the sounds off after 30 seconds once the train is brought to a stop and all the functions are turned off (See page 48).
You can see that function mapping allows you a great degree of flexibility to solve a variety of problems even if your cab is limited to less than 14 functions.
Tsunami Steam Sound User’s Guide