Control of sounds etc with Analogue Loco

Airbuspilot

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I am helping a friend with an (LGB) RhB Triebwagen ABe 4/4 which I am told is Analogue, it does run on a DC track. When DC power applied the various sounds of engines starting, compressor noise, doors operating etc starts, only when the loco is ready does it start to move. If it stops at a station the sounds go silent immediately and it only moves again after all engine starting noises have been competed. The head lights work correctly with direction and there is a light bar in the cabin which is OFF.

My experience is with 00 and N scales and just starting to look at DCC, there is nothing in my own analogue experience to compare with this.

Are the characteristics described normal? Are the various sound effects controllable, can I keep engine noises going when stopped at a station for example?

I have tried to access the digital interface but gave up as it looks like a major strip down to find it and I would prefer to wait until I know a bit more about what I am doing.

If the sounds, internal lights etc. are controllable by CV or equivalent, how are they controlled?

Is there a possibility there is a DCC decoder fitted which we don't know about. Can I put a DC loco on a DCC programming track safely?

Thanks

Robin
 

JimmyB

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Sounds need power, no power to the track, no power to the sound, hence when the loco is at rest there is no sound. Some locos have a 9v battery or capacitor, but this is to allow sound at low voltage before the loco starts to fully move, but again there needs to be track power.
 

Brixham

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Hi, try the railcar on the prog track, if fitted you should be able to read cv1, the loco address.

Alternately, if your doc system supports a single analogue unit, try it on address 0. If it moves, there isn’t a decoder. However, if the sounds start, but the unit doesn’t move, it almost certainly has an integrated decoder.

It may just have been left as an analogue railcar, but fitted with a digital sound unit.

Malcolm
 

PhilP

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Are the characteristics described normal? Are the various sound effects controllable, can I keep engine noises going when stopped at a station for example?
The Buhler motors that LGB use will start turning at 2-3V. The electronics (sounds etc.) will not 'wake-up' until there is 5-6V available..

So, very early (analogue) models would move, before the sounds would start.
To combat this, LGB added electronics in the motor circuitry to not allow the motors enough voltage to turn, until there was about 6V available in the model. - This meant you needed to turn your controller further up, but would get sound before the model moved.

If, as I suspect from your description, there is a decoder in the model, then it can control things even more..

If there is not enough voltage to the loco, you will lose the lights and sound..
Try reducing the controller very gently. - You may find there is a 'sweet-spot' where the model stops moving, but there is still enough voltage to keep the lights on and sounds active.


The only way to keep sound etc. running with a DC controller turned right-down, is either with a battery (some models have provision for this) or a 'keep-alive' bank of capacitors.

Problem with this can be that if a loco has a power-buffer, they can misbehave on a DCC layout, when the power is turned off.


So, yes, you can keep sounds going, but unless the model has reed switches, and you use track magnets, you do not have a great deal of control..

You may find that, if you can bring the loco to a stop with enough voltage to keep the sounds going, that after a time the loco sounds will go through a sequence to stop the 'engine'..

PhilP
 

ntpntpntp

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As described, I'd say that's typical behaviour of a DCC Sound fitted loco running on DC. It requires a minimum "wake up" voltage for the decoder, which then goes through it's start-up routine before setting off. My N gauge DCC sound fitted locos do the same.

Yes put it on a DCC programming track and see if the programmer can detect a decoder. You won't do any damage if there isn't, but avoid running it on the main DCC track if it hasn't got a decoder fitted it's just not worth the risk of damaging the motor on the pseudo-address "zero" (which some systems actually implement on a different address)
 

Airbuspilot

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Thanks for all your info and advice.

Obviously the sound will stop when there is no power on the track should have realised that, been thinking DCC for a while :(

I will try slowly reducing voltage to see what happens.

I will try the programming track to check CV 1 but I don't think its worth running on the DCC layout as it will never be used there. I thought it would make a good DC shuttle as we have plenty of room and a shuttle unit available. If the motor noise stops during the station stop then obviously the driver is having a cup of tea, or whatever Swiss drivers drink.

Robin
 

dutchelm

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Depending on the vintage of the sound unit you may find a 3 pin plug for a battery or capacitor unit. This will keep the sound going for several minutes whilst the passengers board.
 

Airbuspilot

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Thanks Mike

I started to dismantle the railcar but to get at the decoder required a major effort so I stopped. For now I will go with what we have but I will bear this in mind for later. I still have two other locos which are not working to fix as a priority.

Robin
 

phils2um

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There are lots of good help on opening up LGB ABe4/4 railcars on this site. There are some tricks/tips that make it much easier! Do a search.
 

Dan

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All of the LGB stock engines I have worked on had super caps or 9 volt batteries for the sound unit only, not for the engine mot or lights. Zimo on the other hand uses supercaps on one decoder and feeds everything via the decoder. So decoder type can determine how an engine will run. my Stainz will run for over 20 seconds without power due to the 10 farad/2.7 volt supercaps on the internal 16 volt line.