Homemade Japanese DCC Signals

[KenS]

I stumbled across this site via Youtube.  The author is a hobbyist who has designed a couple of combination block-occupancy detector and signal controller boards that can replicate prototypical Japanese (or other) signaling. He's posted a number of videos showing operation, as well as schematics and programs for the controller.  Simply amazing stuff.

 

The Sigaling page on his website:

 

http://wsim.cs.ehime-u.ac.jp/~shimizu/signal2009/signal2009-01.html

 

Japanese system videos:

 

 

 

 

 

 

There are more videos on his site, but the others look like they're non-Japanese prototypes (I haven't watched all of them yet though).

[Fat Al]

Holy carp! That is amazing!

[CaptOblivious]

That really is nice. Even better that the explanatory website is in English!

[to2leo]

Ingenious system.  Though I think I am just going to wait for moving block systerm 

[quinntopia]

Wow.  That's really inspiring.  Well, watching the video's was inspiring...by the time I read down his site to the 'typa b' board explanations I knew this was too much for me.

 

One cool thing -and you electrical geniuses can confirm or deny this - is I was wondering how/where he got all the signals for this system (if you've read my blog, this is something I've been struggling with).  The Captain and some others suggested I use some really tiny SMD LED's-which I now have- but I've been frustrated trying to solder them to wires!

 

Looking at this picture it looks like he solders the LED's to a circuit board, then cuts the pieces out....ingenious if true! Is that right? Sorry, took this thread way off topic....

[rankodd]

That's precisely what he's done - everything looks to have been done on fairly standard protoboard PCB...

[CaptOblivious]

That's precisely what he's done - everything looks to have been done on fairly standard protoboard PCB...

 

Yep, I concur. But notice that now the targets are considerably out of scale!

[quinntopia]

Thanks Rankodd * Capt!  This will be a lot easier than trying to hold 30 gauge wire onto those tiny pads (and soldering).  Even with a third hand, I'm still a hand or two short!  It also explains why some of these bi-color LED's have what appears to be 4 contact pads! Very cool info!

[rankodd]

What I'd expect - or at least what I would do in his place - is to use this technique for building test prototypes. (And that's prototypes in the electronic sense, not the model railroad sense!) After all the bugs are ironed out then I'd go ahead and put the effort into building proper scale representations.

 

Did anyone see what he's using for train detection? I couldn't find anything specific, but I haven't gone all the way through the details yet.

[KenS]

What I'd expect - or at least what I would do in his place - is to use this technique for building test prototypes. (And that's prototypes in the electronic sense, not the model railroad sense!) After all the bugs are ironed out then I'd go ahead and put the effort into building proper scale representations.

 

There are some references to use of Tomix 3, 4, and 5-color signals in the programs, and a picture on one of the Japanese pages, so he may be planning to use those (or just building in compatibility for them).

 

He also has a page on converting the Kato 3-color signal to DCC operation, and this includes a reference to the Tomix 4-color signal.

 

Did anyone see what he's using for train detection? I couldn't find anything specific, but I haven't gone all the way through the details yet.

 

There's a "train detection" element on board "A", which is simply a TLP521 photocoupler.  If I'm reading the diagram and program right, it pulls input RB4 on the DCC decoder PIC low when current is flowing to the rails (it's labeled "stop trigger in" on some diagrams, and "s-in" elsewhere).  See the diagram labeled "1: Type-A element" just below the "How to assemble signal board elements" heading on the English page: the circuit labeled TPS521 is the photocoupler that detects current. It looks like there are multiple generations of his board described on these pages, so that circuit may have changed, and I'm not sure why he'd referencing a TPS521 on the English page (which is some kind of microcontroller, not a photocoupler, as far as I can tell).

 

He says in one place the type A board can have up to three onboard detector circuits (one is typical). However, the board also has inputs for external detectors to supplement the onboard ones (needed with some of his designs for multiple blocks controlling a stop relay) and for a photodiode input (for precise position detection when stopping trains). He mentions use of  the Digitrax BDL16 as a good supplemental detector.

 

I may have misinterpreted some of that, as I'm no electronics whiz, and he didn't document all of the elements clearly (machine-translations of his Japanese pages don't help me either).  But I think I understand the rough outline of what he's doing. Not well enough to build one, but I'm more concerned with understanding how he wants it to work, than with making one.

[rankodd]

What I'd expect - or at least what I would do in his place - is to use this technique for building test prototypes. (And that's prototypes in the electronic sense, not the model railroad sense!) After all the bugs are ironed out then I'd go ahead and put the effort into building proper scale representations.

 

There are some references to use of Tomix 3, 4, and 5-color signals in the programs, and a picture on one of the Japanese pages, so he may be planning to use those (or just building in compatibility for them).

 

He also has a page on converting the Kato 3-color signal to DCC operation, and this includes a reference to the Tomix 4-color signal.

 

Did anyone see what he's using for train detection? I couldn't find anything specific, but I haven't gone all the way through the details yet.

...

 

Thanks! I was looking for photodiode sensors and didn't see any :( I had considered using current flow for block occupancy detection, but hadn't realized that it was an established technique.

 

The BDL16 (now BDL168) he talks about is $125! DCC is so expensive. :( I want to put signals on my layout as a way of increasing the blinkenlight density but DCC costs too much and signals are quite complicated to do otherwise. The fact that you can build a DCC decoder using PICs seems like a nice way to get around the expense, but I can just see myself puttering with electronics for months on end instead of running trains :(

[nik_n_dad]

He also has a page on converting the Kato 3-color signal to DCC operation, and this includes a reference to the Tomix 4-color signal.

 

I've ran across this page before.  We have a number of the kato 3-signals that we'd like to use on the upcoming new\big DCC layout, but The translation of the page (for me anyway) is virtually unreadable, so I haven't even tried.  Has anyone here converted the kato signals for DCC use?