# Basic Programming

larger values for these CVs; we therefore suggest setting CV 3 and CV 4 to a minimum value of 16 or higher.

If you are using 14 or 28 Speed Step modes, setting CV 3 and CV 4 to any value greater than 0 will also improve the Tsunami’s throttle response. While it is accelerating or braking, Tsunami interpolates between speed steps so in effect, your locomotive will respond as if it were being controlled with 128 speed steps. No more sudden lurching from one speed step to another!

## Select the Speed Table

Tsunami provides 14 preset and one loadable speed table that can be used for several purposes:

1.

Matching the Auto Exhaust chuffing rate to locomotive speed.

2.

Speed matching one locomotive to another.

3.

Changing the feel of the throttle. For example, you could configure a switching locomotive so there are more speed steps available at lower speeds for switching and fewer steps at high speeds where the locomotive is seldom operated.

4.

Compensating for an improperly designed driveline so the locomotive will operate within its prototypical speed range.

Preset Speed Tables CV 25, Speed Table Select, is used to select which speed curve will be used by the DSD. CV 25 may be programmed with any value between 2 and 15 to select one of the preset speed curves shown in Table B, below.

100%

## Table B. Speed Table Selection

2

Straight LIne

3

Logarithmic Curve 1

4

Logarithmic Curve 2

5

Logarithmic Curve 3

6

Logarithmic Curve 4

7

Logarithmic Curve 5

8

Logarithmic Curve 6

9

Logarithmic Curve 7

10

Exponential Curve 1

11

Exponential Curve 2

12

Exponential Curve 3

13

Exponential Curve 4

14

Exponential Curve 5

15

Exponential Curve 6

16

User Loadable Speed Table

CV 25

Speed Curve Type

Motor Speed

75%

50%

25%

0%

0

2

### LOG 7

### LOG 6

LOG 5 LOG 4

LOG 3 LOG 2

### LOG 1

### LINEAR

### EXP 1

### EXP 2

EXP 3 EXP 4 EXP 5

### EXP 6

4

6

8

10

12

14

16

18

20

22

24

Speed Step

26

28

## Tsunami Steam Sound User’s Guide

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