[Mike Robbins]

Hello.
I am new to forum but can anybody answer my question
Here goes.
I want a enable a loco to automatically reverse on a single run of track, say 3mts long. The track will be isolated from all the other track on the layout and runs under DCC.
The idea is that when the loco touches a buffer stop It will automatically reverse until it again touches the other buffer stop and then reverse again.
Can anybody help me please

 

[duffer]

I think that what you are looking for is a "shuttle" device Block signalling make one , here's a link , http://www.blocksignalling.co.uk/index.php/simple-shuttle-ss1

 

[Mike Robbins]

I think that what you are looking for is a "shuttle" device Block signalling make one , here's a link , http://www.blocksignalling.co.uk/index.php/simple-shuttle-ss1

Thnx Duffer. Exactly what I am looking for.

 

[Nigel2001]

Thnx Duffer. Exactly what I am looking for.

Unfortunately I think you may have duff answer above. You asked for a DCC layout. The item works on DC, not DCC. Mixing DC and DCC on the same layout is risky ("pfff" goes your expensive control gear) if there is ANY possible way the turnouts could be set to connect the rails together.

For DCC there are multiple solutions, but it depends on what decoders, or which maker's system you have on the layout.

Simplest decoder option (any DCC command station): A decoder in a loco which supports an automatic shuttle behaviour (loco passes detector, slows down gradually to a stop, waits for a pre-set time, reverses direction, accelerates away. At other end, passes detector, slows down.....). Lenz is the simplest, they have the feature built into their decoders. The trackside trigger device at each end to begin the behaviour are "BM1" modules, you need two of them, one for each end. (BM1's are just six fast-recovery rectifying diodes if you want to make your own for about 50pence).

Simplest command station dependent options (any decoder): NCE: the NCE MiniPanel, but will be tied to a specific loco decoder. Digitrax (and any system which accepts LocoNet/Digitrax throttles, such as Digikeijs, Roco Z21): CML/Signatrak DSS1 shuttle device, which can do complex sequences. Both require a track-side switch of some sort to detect the presence of the loco, such as breaking an optical switch breaking an IR beam as the train passes. There are many other options covering other maker's systems, doing it with some computer software on a RaspberryPI is a cheap option (using the PI's GPIO pins to connect the track detectors to the PI).

 

[duffer]

Unfortunately I think you may have duff answer above. You asked for a DCC layout. The item works on DC, not DCC. Mixing DC and DCC on the same layout is risky ("pfff" goes your expensive control gear) if there is ANY possible way the turnouts could be set to connect the rails together.

For DCC there are multiple solutions, but it depends on what decoders, or which maker's system you have on the layout.

Simplest decoder option (any DCC command station): A decoder in a loco which supports an automatic shuttle behaviour (loco passes detector, slows down gradually to a stop, waits for a pre-set time, reverses direction, accelerates away. At other end, passes detector, slows down.....). Lenz is the simplest, they have the feature built into their decoders. The trackside trigger device at each end to begin the behaviour are "BM1" modules, you need two of them, one for each end. (BM1's are just six fast-recovery rectifying diodes if you want to make your own for about 50pence).

Simplest command station dependent options (any decoder): NCE: the NCE MiniPanel, but will be tied to a specific loco decoder. Digitrax (and any system which accepts LocoNet/Digitrax throttles, such as Digikeijs, Roco Z21): CML/Signatrak DSS1 shuttle device, which can do complex sequences. Both require a track-side switch of some sort to detect the presence of the loco, such as breaking an optical switch breaking an IR beam as the train passes. There are many other options covering other maker's systems, doing it with some computer software on a RaspberryPI is a cheap option (using the PI's GPIO pins to connect the track detectors to the PI).

Nigel , Mike said the section of track in question will be "isolated" from all other track ie the DCC track , if so then a simple DC shuttle unit is an easy and cheap way to get what he requires .

 

[Nigel2001]

Nigel , Mike said the section of track in question will be "isolated" from all other track ie the DCC track , if so then a simple DC shuttle unit is an easy and cheap way to get what he requires .

Yes, I read that. "Isolated" often means "couple of plastic rail joiners", or "turnout set against using turnout power routing". Both are high risk. Park a loco, or any other vehicle with metal wheels, over the insulated joiners and you've risked a "pfff" event in the systems. For mixing, the track needs to have no chance of running between the two, even by pushing the stock along the track.

The DCC solutions give better running and don't introduce the risks of stuff going wrong, or require the track to be fully independent of the rest of the layout. Unless there's a spare DC controller lying around to be used, the DCC solutions are cheaper than the DC solution (because a DC controller has to be bought and dedicated to the task).

 

[duffer]

You obviously have better experience than me so i'll bow to your solution .