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But, we are talking about a trolley reverser. DC or DCC, the function is Stop at the End-of-Line terminal, Delay, Reverse back to the Home terminal. like the Bachmann or Miniatronics (I think) units for DC. I think it needs better logic than those.
 

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Azatrax makes a reverser that controls a trolley that goes back and forth
between stations at the two ends of the line.


It would work just as well
to control a train doing the same. Only problem is, the train would
be backing up on it's return. You could make it a typical commuter
train similar to those operated in and out of many cities. These have
a loco at one end and actually do back up on their return trip.

Don
 

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As Severn mentioned above, this can certainly be done with DCC++, or probably any system with a JMRI interface. I set up something a couple months ago will testing the electronics for the shelf layout I'm building, however my setup was probably overly-complicated for what OP wants. I used a DCC++ command station with wifi, an arduino nano set up for an S88 bus, a couple pairs of IR LED sensors to detect the train reaching the end of the ilne, and a script I wrote up on my desktop computer to read the JMRI interface. I was actually testing a lot of pieces I'll eventually build into my shelf layout, but if you only want a simple back-and-forth then this is way more than what is required.

Realistically this could all be done with a single arduino, the IR LED detectors, and an L298 H-bridge to control DC to the tracks. (It could be done with DCC++, but you'd have to understand the code well enough to know where to insert your own extra bits.) Basically you use one of the PWM outputs from the arduino to control the L298, which would give you speed control. The IR sensors are placed near the end of the track and when the arduino sees one of them triggered it stops the train and reverses direction. To really do it up right you could put the sensors a foot or so back from the end of the track, which gives you time to slow down before stopping.

Sheesh... I'm realizing that even though this sounds dead-simple to me, it must be very confusing to someone who hasn't worked with arduinos before. Sorry about that. It really is straightforward with a minimum of components, the programming can be done from any desktop or laptop computer, and it could probably be built for under $20.
 

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I like it! This sounds really doable... You can have realistic accel/decel and possibly even ring the bell/blow the horn...
when Zodiac comes back in maybe he will give us some feeling for his comfort level with all this... 😅
No train yet!!!!
 

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Yeah if you want all the fancy sounds and features that DCC provides you can still set up DCC++ and have some free I/O ports to monitor the IR LEDs. That would also give you the option to consist the front and rear loco together so you could do proper speed-matching. You could even turn off all the lights on the 'dead' loco so it appears to simply be pulled along.

If anyone wanted to look into this further, it would probably be worthwhile to check the DCC++ forum, as I would be surprised if someone hasn't already created the code changes for such a setup.
 

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"Auto reverser" in DCC terms usually means that as the Loco crosses to an isolated section, if the track phase is wrong (causing a short circuit) the device detects this short and automatically swaps the phase of the track under the loco. The Locomotive continues on in the same direction as the detection and swap occurs very fast. These are used in reverse loops to correct the phase miss-match, not reverse the locomotive. These devices send no DCC commands to the locomotive.
Normally, this is correct, and in tha absence of any clarifying text in the item description I would assume that's what you're looking at. The item linked by prrfan fits in that category.

But the ones linked by cid and severn are what the OP is looking for. Another option is the Train shuttle card fromTam Valley Depot. It's out of production, but you may find one on eBay or other auction sites.
 

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Discussion Starter #30
I think OP said he would have a loco on both ends...
Cid, et al, ----- (did you ever feel like a chimpanzee thrown out onto a basketball court full of Michael Jordan's?) lol, cause that's what I feel like. Ya'll are just talking a language that I do not know. At all.

Cid described it best IIRC, just want a realistic looking loco pulling some rolling stock down a LOOONG straight track. When it gets to the end, it should slow down in a realisitc manner (vs just stopping on a dime) and then come to a stop. All the bells and whistles (literally) should be there as well as it's coming to the end of the line........

The ONLY reason for wanting 2 locos is simply for looks....... sooner or later the train is going to have to "reverse" itself and reverse all the way down the length of the track until it gets back to the starting point. It would LOOK might stupid to see a train going in "reverse" down that long straight track.........UNLESS.......there was a loco on both ends. That way , it gives the appearance of going forward and thus not looking stupid.

It could absolutely be a "dummy" loco for all I care. So long as the appearance of forward motion is achieved........

Seems to me the only hard part about this project is getting the > stop > delay > reverse thing settled and that's where I'm stuck. I'll look at some of the products that have been listed.

Side note: I find it really strange as long as this hobby has been around, there STILL is no simple answer for this. That's an aggravating head scratcher to me. Such a product would completely eliminate the need for a "loop" and thus free up massive space.......in theory.
 

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Discussion Starter #31
As Severn mentioned above, this can certainly be done with DCC++, or probably any system with a JMRI interface. I set up something a couple months ago will testing the electronics for the shelf layout I'm building, however my setup was probably overly-complicated for what OP wants. I used a DCC++ command station with wifi, an arduino nano set up for an S88 bus, a couple pairs of IR LED sensors to detect the train reaching the end of the ilne, and a script I wrote up on my desktop computer to read the JMRI interface. I was actually testing a lot of pieces I'll eventually build into my shelf layout, but if you only want a simple back-and-forth then this is way more than what is required.

Realistically this could all be done with a single arduino, the IR LED detectors, and an L298 H-bridge to control DC to the tracks. (It could be done with DCC++, but you'd have to understand the code well enough to know where to insert your own extra bits.) Basically you use one of the PWM outputs from the arduino to control the L298, which would give you speed control. The IR sensors are placed near the end of the track and when the arduino sees one of them triggered it stops the train and reverses direction. To really do it up right you could put the sensors a foot or so back from the end of the track, which gives you time to slow down before stopping.

Sheesh... I'm realizing that even though this sounds dead-simple to me, it must be very confusing to someone who hasn't worked with arduinos before. Sorry about that. It really is straightforward with a minimum of components, the programming can be done from any desktop or laptop computer, and it could probably be built for under $20.
I don't even know what arduinos is..... ?? Never head of it until I came here. Uggg. The dream is slipping away. lol.
 

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Zodiac, we really have no idea of your knowledge or level of comfort with electrical devices.
You are wanting automatic speed and direction control of the train(s) which are basically DC motors.
There are several schemes and products like we have listed to let you do this simply.
 

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To take it up a level, like realistic deceleration and sound effects, will require more logic. I suggest you start on a layout, look at train hardware, and save the finer points of control for later when you can actually see it run.
 

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I interpreted the need as being a forward and reverse direction DCC commanded engine (train) on a straight or non looping track hugging a wall. So the train starts at one end... Goes forward towards the other...and then is commanded to reverse backwards over the same track before it smashes into the end. Repeat.
 

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One reason why I don't like point-to-point layouts. Instead of watching trains run you have to constantly stop and reverse the train to go back to where it came from.

But some folks like all of the switching and track changes of a point-to-point, and that's fine too. Me? I'd rather just throttle them up and watch them run through the scenery and villages with a minimal of switching except to change trains.
 

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Zodiak

I feel your pain. It appears we have all been talking shop, using 'terms'
that you possibly had never heard. We need to stop and and bring you
up on the basics.

HO locomotives run on track powered by Direct Current 'DC'. (discussion
of DCC is for another time, ignore it now).

The current is supplied by the Power Pack 'track' terminals. The
current is polarized...one wire is PLUS the other NEGATIVE. These
are connected to the track, PLUS to RIGHT RAIL, NEGATIVE to
LEFT RAIL.

The Power Pack usually has two controls: The FWD / REV
SWITCH and the SPEED CONTROL knob.

When the switch is set to FWD and Speed knob raised,
the loco moves forward, and when
set to REV the track polarity is REVERSED and the loco backs.

With a 'POINT TO POINT' track, with no loops at the ends,
a loco will always be pointed in the same direction. Using
the FWD/REV switch it will 'back' to the starting point.

I do agree with you that a loco backing a train is not
a desirable attraction. I have two suggestions.

1. Run a 'commuter' passenger train. As I've said before,
these are on tracks like you propose with no loops. The
loco runs FWD in one direction, and Backs the train.
This can be AUTOMATIC using the Azatrax device I
linked to earlier.

2. Arrange a second track at each end,
connected by turnouts, that
permits the loco to 'run around' the train (either
passenger or freight), and thus
'Pull' it back to the starting point. To make this more
believable, use two identical diesel locos connected
together 'tail to tail'. Thus one loco is always facing
Forward. Though a very complicated electronic system
could be made to control this, it would be quite costly.
You would best be advised to run it manually with
you at the controls.

Don
 

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I don't even know what arduinos is..... ?? Never head of it until I came here. Uggg. The dream is slipping away. lol.
Well, none of us were born knowing all this either. We all had to learn it. We're not trying to blow fastballs by you, but as cid said, we really don't know what you know. So if you don't understand, ask. No one will think less of you (in fact, the problem children are the ones who refuse to learn...). Or look it up yourself. I'll spot you one: Arduino - Wikipedia

Side note: I find it really strange as long as this hobby has been around, there STILL is no simple answer for this. That's an aggravating head scratcher to me. Such a product would completely eliminate the need for a "loop" and thus free up massive space.......in theory.
This is why you're confused, really. The average model railroader doesn't want the trains to run by themselves. We want to play with them, and that means controlling speed, direction, lights, sounds, etc. Setting up automatic control really isn't rocket science, but it's enough outside the mainstream that you'll have to put a little work into it. Most layouts have loops, because that keeps the loco on the front of the train in normal circumstances, so it operates more like the real thing (real trains don't just endlessly run back and forth, especially freights). Quite a few layouts do not have loops, though. These are known as point-to-point operations, and they are an even more realistic simulation of an actual train. Trains leave a point at one end of the layout, run through they layout, stopping and dropping off or picking up cars as appropriate, and end up at the other end. Once all trains have traversed the layout, the operating session is over. Most of the time, the trains are manually turned to prepare for the next session.
 

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Honestly Zodiac, the specific thing that is complicating this for you is the desire for the acceleration/deceleration feature on your reversing line.
If you were willing to forego that, setting the DCC system up with the equipment DonR has suggested would not be difficult.
Yes, this feature is more realistic than going from speed to a dead stop, and vice versa, but it will be challenging to construct it because no, it does not exist as an out of the box system per se.
I had two reversing lines on a switching layout and I loved them. It creates constant motion while you are running your switching operations on other tracks.
So, challenging but not impossible. There are certainly folks on here to help you if decide to do it. Best of success and keep us posted.
 
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