DCC and Automatic Reverse Circuit

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This is my 1st post on this forum. I have an HO DCC trolley. As a small part of my overall layout, I want to run the trolley on a straight point to point track. When it reaches either end of the track, I want the trolley to stop, pause and reverse direction. Back and forth. Nothing fancy. My question is this: I have a Circuitron Automatic Reverse Circuit (AR-2) and a couple of Circuitron Opto-Sensors (tiny, light-sensitive photcells to be mounted in the roadbed, so that they will be shaded from ambient room light when the trolley passes over). I bought them years ago. Will the AR-2 and Opto-Sensors work with DCC (i.e., stop, pause and reverse the trolley)? If not, how should I accomplish this? Thank you in advance for any help anyone can offer.
 
Welcome to the forum, nice to see "new" modellers, as for your query, Sorry I'm no help with that, but someone will be along who will be able to give you some help.
 


What about a very narrow double track system with very sharp balloon curves on each end..You'd still reverse direction but without any special electronics...
 
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Thanks for taking the time to respond. I actually built that. As a standalone removable unit. Still have it. This is my 1st layout. Wish I had done L-girder with risers. Anyway, the standalone arrangement worked fine, just didn’t look right on the layout. Also difficult to reach. I’m limited where I can position the standalone. Your response is causing me to re-think that. I’m still hopeful someone can tell me if the AR-2 and opti-sensors will work with dcc, even if I don’t adopt that for this particular purpose. I’ll attach a few photos. Thanks again.
 

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I have an HO DCC trolley. As a small part of my overall layout, I want to run the trolley on a straight point to point track. When it reaches either end of the track, I want the trolley to stop, pause and reverse direction. Back and forth. Nothing fancy. My question is this: I have a Circuitron Automatic Reverse Circuit (AR-2) and a couple of Circuitron Opto-Sensors (tiny, light-sensitive photcells to be mounted in the roadbed, so that they will be shaded from ambient room light when the trolley passes over). I bought them years ago. Will the AR-2 and Opto-Sensors work with DCC (i.e., stop, pause and reverse the trolley)? If not, how should I accomplish this? Thank you in advance for any help anyone can offer.
Short answer is no. All an AR-2 unit does is reverse the polarity of the track connected to the A and B terminals. Reversing the "polarity" of a DCC signal will not reverse the direction of any unit powered by it. You need something that will send a signal to the decoder telling it to reverse the polarity of the motor.

Why is the trolley DCC? Are you going to run multiples of them on the same track at the same time?
If not, I think the easiest way to do it would be to convert the trolley to DC and use the AR-2 and DT-4 as designed by Circuitron.

Other than that, there are many computer interfaces to DCC and related controling software products. Unfortunately, while I have many of the interfaces. I have only designed one software throttle a long time ago on technology now considered obsolete (RailCommand).
Possibly build your own dcc command station and scripts with something like DCC-EX. It is open source.
 
Short answer is no. All an AR-2 unit does is reverse the polarity of the track connected to the A and B terminals. Reversing the "polarity" of a DCC signal will not reverse the direction of any unit powered by it. You need something that will send a signal to the decoder telling it to reverse the polarity of the motor.

Why is the trolley DCC? Are you going to run multiples of them on the same track at the same time?
If not, I think the easiest way to do it would be to convert the trolley to DC and use the AR-2 and DT-4 as designed by Circuitron.

Other than that, there are many computer interfaces to DCC and related controling software products. Unfortunately, while I have many of the interfaces. I have only designed one software throttle a long time ago on technology now considered obsolete (RailCommand).
Possibly build your own dcc command station and scripts with something like DCC-EX. It is open source.
Thanks. I understand. Am I going to run multiple trolleys on the same track? No. Then why is the trolley DCC? The short is because I was dumb when I bought it. Having a DCC system, I thought I needed a DCC trolley. It didn’t occur to me at the time that it would be cheaper and easier actually to just power a DC trolley with a spare DC transformer rather than running it on the DCC system. Oh well.
Thanks for straightening me out and also for doing it in a manner that wasn’t way over my head. I’m glad I discovered this forum.
 
This may well be wrong, but I do sometimes have ideas that are so left field as to be out of the park, so I'm not sure this idea would be possible. If you run a separate power supply, make the trolley DC. and fit micro switch's either end that would change the polarity on the track so the trolley would reverse, would that work??
 
Awesome looking buildings in those layout pics as well by the way!
Thanks.
This may well be wrong, but I do sometimes have ideas that are so left field as to be out of the park, so I'm not sure this idea would be possible. If you run a separate power supply, make the trolley DC. and fit micro switch's either end that would change the polarity on the track so the trolley would reverse, would that work??
I may be wrong (not the first time) but I think that’s basically what Iron Horseman was suggesting.
 


You can do this with a DCC trolley. There are Youtube videos on how to use an Arduino and block detectors along with DCC++ to not only stop and reverse the trolley but to also make it stop, pause, and go at intermediate stations.
 




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