# LGB Decoder III



## gdancer (Feb 19, 2008)

I have an NCE Power Pro 10 amp system that permits programming "on the main". H/e, my efforts to program on the main the LGB decoder III on my LGB Forney does not appear to have any effect. Can LGB III decoders be programmed on the "main", or just on a programming track? Any help greatly appreciated. Also, how to prevent LGB decoders lights from being on only on even speed settings when operating on 28 steps or must program back to 14 steps? Thanks!


----------



## rwbrashear (Jan 5, 2008)

GDancer, 

LGB decoders do not offer Operations Mode Programming (a.k.a. Programming in the Main). CV changes require a programming track.

The headlights are flashing because your NCE system is sending 28/128 speed step commands and the default setting for your LGB decoder is 14 speed steps. (If you have an older EPROM in your NCE command station, you may be able to select 14 speed steps. This mode was eliminated on more recent EPROM updates.) In 28 speed step mode, the central station uses the lighting bit for the additional steps. For even speed steps, the lighting bit is set 'high.' As a result, if the decoder is looking for 14 speed step commands, it decodes the even speed step instructions as a lighting commands to turn on the headlights. The opposite happens for odd number speed steps.

Reprogram CV#29 on your MTS III decoder to enable 28 speed steps to correct the issue. The default value for CV#29 is [4]. Change this value to [6] to correct the issue.

If you really want to understand the 'nuts and bolts' reason why the lights flash, read through page #2 of the attached document. 
http://www.nmra.org/standards/DCC/s...004-07.pdf

You will need to use the programming track to make the change. When using NCE to program LGB decoders, I have the best success using Direct Mode Programming. Depending upon the installation, you may need to have the power control switch in position [2]. (Lights/Motor are ON and the Sound is OFF).

Good luck!

Best regards, 
Bob


----------



## gdancer (Feb 19, 2008)

Bob..... Thanks! That was a greatly detailed answer but I needed every bit of it. Will let you know how I fared.


----------

