KB934: CV50- CV52, CV62-CV63 & CV113-CV116 FX3 Special Light Effects

Decoders with FX3 features have 8 user configurable, independent special effects generators.  All current production Digitrax Decoders use FX3 function features. 

These are set up by programming CV values as described below.  If your decoder is not a Series 3 decoder, please check the spec sheet to determine which type of functions it supports.

FX3 functions incorporate FX generators with additional dynamic and static qualifiers.  FX3 functions are fully remappable so they can be controlled by any function key on your system.  A master light switch can be set up to turn off all lights on a locomotive. Functions associated with advanced consists can be controlled, too.

Setting Up FX3 Effects On Function Outputs

1. Each function output has an FX3 control CV associated with it. Using the table below, determine which CV you need to program to set up an FX3 feature for the function output you are working with. For example, if you want to set up an FX feature on your forward headlight, you will use CV49 to control the FX3 feature for the lamp attached to F0F.

Some decoders do not have function output wires attached. See the specific decoder instructions to determine which "pad" on the decoder controls each function. Use thin wire or wire saved during previous decoder installations to solder function output wires to the pads associated with the function you want to use.

FX3 Generator CV's:

NOTE: Decoders with FX function generators use different CVs to control function outputs.  

2. Each FX3 effect has a CV value that generates the effect you want and controls how the effect works with respect to locomotive direction and the head light (F0) function.

The FX3 CV value is made up of 2 digits. The second digit determines which FX3 effect will be generated. The first digit determines how the effect will work with respect to the locomotive direction, the head light and other functions. Use TABLE IVb to determine the second digit and Table IVc to determine the first digit of the FX3 CV value to program into the CV selected in step 1.

Second Digit Values:

The Second digit of the FX/FX3 CV value determines which FX3 effect will be generated.

First FX3 Hex Digit Values:

The first hex digit of the FX3 CV value determines how the effect generated will behave.

For example, two strobe lights can be set up to flash alternately by setting one to phase A and the other to phase B. The strobes can also be set up to be on when the loco is moving forward and off when moving backward.

How FX3 effects generated will work:

3. Program the FX3 CV value from step 2 to the FX3 CV identified in step 1.

If you are using the PR1, an FX set up section is available where you can just "point and click" to set up the effects you want to use. The software lets you select which function output and which FX feature you want from a menu so you don' have to use the tables above to determine which CV or CV value to use.

4.  For FX3 decoders, you can set up as many as 8 function outputs. All FX3 outputs can be set up with FX3 effects.

5.   If you want any function output to remain a simple on/off output, leave it programmed to the factory default of CV value 00.

Customizing FX3 Effects-Rate and Keep Alive (CV62)

CV62 lets you control the rate and keep-alive brightness for each FX3 effect you set up. The CV value for CV62 is made up of 2 digits, the first digit and the second digit.

The first digit controls the keep alive/baseline off voltage for incandescent lamps. This value should be between 0 and F. A value of 0 gives no keep alive and a value of F gives maximum keep alive. Values between the high and low allow you to vary whether the lamp actually goes off between light pulses or whether it stays on very dimly or more brightly. (If you are using LEDs, the first digit for CV62 should be 0.)

The second digit controls the rate of the FX3 effects programmed. This value should be between 0 and F. A value of 0 gives a fast rate and a value of F gives a slow rate of operation. We recommend you start with a 4 and adjust it up or down until you get the effect you are looking for.

Ditch Light Hold Over Time (CV63)

If you are using the ditch light effect in conjunction with F2, CV63 lets you set up a hold over time to control how long the ditch lights continue to blink after F2 turned off by releasing the key on the throttle. Remember that F2 is a momentary key on most Digitrax throttles that will keep function 2 on as long as you hold the key down and then turn function 2 off when you release the key. This allows the ditch lights to be on steady during regular operation and to begin alternate flashing when F2 (usually the horn) is activated and to continue flashing alternately for a predetermined length of time after F2 is released; just like the prototype. A value of 00 yields no hold over time, a value of 40 yields a realistic time of about 5 seconds. A value of 255/xFF yields about 20 seconds hold over time.

FX3 Examples

Any function output on the decoder can be set up for any FX3 effect by programming its associated FX3 CV to the appropriate FX3 CV value. For example, if CV52, the FX3 CV for F2, is programmed with an FX3 CV value of 002/x02, the violet F2 function output will be a Mars light when F2 is turned on for this decoder address and the decoder's direction is forward.

FX3 CV EXAMPLES:

CVs that affect all FX3 function outputs:

CVs that affect specific FX3 outputs:

To set up two alternating double pulse strobes on the green and violet function outputs controlled by turning on both F1and F2, program CV51 to a CV value of 037/x25 and program CV52 to a CV value of 053/x35. This is an example of using the alternate effects phases A & B.

For FX3 decoders you have 8 FX3 generators available to use with your function outputs.

Setting Up Static (Non-FX3) Functions with FX3

When an FX3 decoder output is set up for static on/off operation (no FX3 effect), you can use static qualifiers to customize the operation of the on/off function of that output.

In this case, the second digit of the FX3 control CV will always be 0 to set the decoder for static (no FX3)function operation. The first digit is determined by the following table ccording to how you want it to work.

Troubleshooting FX3 effects

Common problems with FX3 set up are:

Trying to program a decoder for FX3 when the decoder does not support FX3.

Be sure the decoder you are programming has FX3 features. Digitrax introduced FX3 in 2002 in the Series 3 decoders. Digitrax introduced FX in the summer of 1995 in all of its premium decoders so if your decoder was made before then it does not have FX capability. FX & FX3 use different CVs for controlling the function outputs of the decoder.

FX3 effects don't work as expected.

Review the qualifiers you set up for the effect. For example, if the effect is set up to come on only when F1 and F0 are active and the loco is headed in the forward direction, be sure you have met those conditions.

Setting Up A Master Light Switch with FX3 Decoders:

For FX3 decoders F0 can be used as a master light switch to turn off all lights in the locomotive when F0 if OFF.  To do this set up all functions qualified to be on when F0 is on and off when F0 is off.  See table above and use 4, 5 ,6, 7 ,E, or F as the first digit of the FX/FX3 control CV to enable the master light switch on F0.