Cab car directional lights and horn

[Canalligator]

I have a commuter train that is operated push-pull. I have an F40PH on the head end, and an unpowered Metroliner cab car on the other end. The F40 has a Tsunami2 decoder in it, and I’m going to install a sound and light decoder in the cab car, Soundtraxx 829100. I am initially planning to configure both decoders to the same address, i.e. take the easy way out - but I will use consisting if necessary.

I presume you can do directional headlight and reverse lightin the cab car like you do them in the locomotive, by just wiring to the headlight and tail light connections. And I see there is a way to make functionlights operate directionally for the strobe or ditch lights.

My question is, is it possible to configure the horn to operate only when the applicable unit is going forward? In a first reading of the manuals, I don’t see what CVs you would configure to do this.

 

[diesel]

Don't the trailing units in a DCC consist have an alternate profile? I think that is what you would usually want, although direction gives you most of it. Trailing units, helpers, and pushers all have different lighting configurations in prototype, than the lead unit. Also those profiles on the prototype, depend on the jurisdiction and road. I don't know very much about consisting in DCC, only tried it once to see how it works. But if there is a way to designate a lead unit ("cab" unit) vs. a consisted or remote unit, in the consisting system, then it should be possible to specify both a "lead" and "trailing" lighting and horn profile for each respectively. That should happen in the locomotive so if it's not already in the spec it may be a good idea to add it. Because your situation is not unlike many others, as I have listed, not just an unpowered cab like the Metra, but all cases of units that are not in the lead.

I'm not quibbling but suggesting a difference, prototypically, not only the horn setting but prescribed lighting setting, such as light intensity and selection are very different from the unit in lead position. For example, a trailing unit might have it's lights always off, or always dim in both directions, on CP trains at least, a pusher would have the headlight facing the rear dimmed. Notwithstanding the differences, these don't prototypically follow the train direction at all. The headlight and horn would remain with the designated lead cab regardless of the direction of the train, because that is where the crew is. That has more to do with properly designating unit functions in a consist, than with the direction of the train.

(a train that is temporarily backing up will have a crew member stand on the back deck with a radio, the headlights do not change. A simple change of direction doesn't suggest whether the train has had its lead unit changed. That is most likely the case with a Metra train when it reaches the end of the line and prepares to reverse on the main)

Your specific case may allow you to overlook the difference because the train makes no reversing moves. But the approach to consisting that I suggested (postulated?) would do that, but also solve a lot of the other problems with configuration of non-lead units. It's possible, that the system already does that, I've been away from DCC for quite a while and in fact many features were added in the time I was gone.

 

[RhB Michael]

I can't tell you anything about the sound in your control car, but for the lighting, I keep them separate for push-pull operation. When I change direction of the train, I change direction of the control car and of course the lights then change too.

Consisting the two together doesn't always work without reprogramming one or the other so the lighting will match the direction. Not all control car lighting is set up identically to locomotive lighting (even though you'd think it should).

As an example, if you have high and low beam lighting on the locomotive and the control car and the control car is consisted to the locomotive, how will you work the high beam headlamps if the control car is leading and the locomotive headlights are not on?

 

[diesel]

I'm only talking about what SHOULD happen. It shouldn't matter that the lighting setup is different in a control car vs. a locomotive. Each one should have a "profile" (which in reality is just set by the jostlers/crew), and that profile has along with it, two configurations, one for leading and one for non-leading. The same can be said for trailing locomotives. That profile doesn't need to be set more than once. The only thing that needs to change is the designation of leading unit. That's a consisting property, and each unit should store a leading and non-leading profile. When a consisting operation is performed, the unit that is designated as the lead unit should load its leading profile, and all other units should load a non-leading profile. In that case, the high beam headlights (and the horn) will automatically be selected on the unit that has been designated as the lead unit.

I don't know if this feature is available but I think it should be. Because all that fiddling with lights and other accessory functions that differ between leading and non-leading units, does not have to be repeated constantly every time the train is reconfigured on the layout. If it were the case, all those changes would take effect with the simple act of breaking the consist and making it again, but with a different lead unit.

It's less important with a cab car than with a multi unit powered consist because the motive power is only in one unit. But if it isn't consisted, all the lighting and accessory function commands will go to both units and you can't control them independently (such as when consisting is done at the command station). I admit, I'm not sure whether lighting and other functions automatically affect only the lead locomotive (I haven't perused the DCC spec in years, really need to catch up...) but I would expect that to already be the case. Then, forming a consist with the locomotive and cab car decoders should already get you close to the right lighting control. Whether it is fine grained enough to control the horn, I don't know. In that case, it's similar to what I'm talking about, except, the non-leading unit functions just turn off instead of following an alternate configuration.

 

[Canalligator]

You may speculate on how things ought to be, but I’m asking a specific question on how they actually work.

There is no overarching “profile” that specifies behavior of an engine. There are CVs that control specific behaviors. You can consider the collection like a profile, but there is no profile structure as such.

For example, you can control function outputs, usually used for lighting, in each unit of a consist using CVs 21 and 22. Two bits in CV 22 are directional. The horn is not an external device like an LED or a bulb. I don’t find similar CVs for sound, just for the lighting.

 

[Canalligator]

I sent an inquiry to SoundTraxx.

Then I did more research. I think I found the answer and I don’t like it. The sound car decoder manual says that I should set CV 129 to 0 to mute the horn on the applicable unit. Sounds like I need to select the loco, mute its horn using CV 129, select the cab car, enable its horn using CV 129, then select the consist again. And vice versa to go the other way.

I don’t think so Tim.

I investigated using macros on my NCE system. It looks like the only thing you can do with macros using a ProCab system is to control accessories. Not CVs.

Unless SoundTraxx as a better idea, I guess I’ll just let the bell and horn work on both ends.

 

[diesel]

Look on P.68 of the Tsunami2 Diesel users guide, "consist example". It does seem from the information there, that you can make effects dependent on direction. The detailed how-to is in "Detailed Function Mapping", P.55. Unless I'm mistaken, from setting those CV's, you could set one cab bell and horn in one direction, and other cab bell and horn in the other direction. Armed with this reference, you might get more specific help from SoundTraxx.

 

[RhB Michael]

That would be an easy fix with ESU.

 

[Canalligator]

Diesel, I read further and found that directional feature information, but thank you for the pointer. I also found the Extended Function Mapping, up in the indexed CVs. That looks like I can implement directional horn and bell on a single function key each.

I’ve started the conversion. I did the design work first. There is a generous cavity in the bottom of the car that has room for the decoder, and I think the speaker too. Current keeper will go in the end opposite of the cab, and I’m getting an interior light assembly that should be a direct hook up to track power. I had to fabricate power pick ups on the trucks, that’s done.