The ABS Signals Circuit Board (289)

[@daleroth236]

I hand built a circuit board several years ago when this article came out, and I was surprised how simple it is to put together, and it worked as illustrated.

[@TheDCCGuy]

One or two isn’t bad but when you need twenty or more then it is a pain in the butt! But I now have more boards than I need and soldering them up is easy and less likely to have any issues.

[@daleroth236]

@@TheDCCGuy Another alternative is to use breadboards when testing your circuits.

[@jhoodfysh]

Well done Larry, I really like the detail and the effort you make to ensure your viewers have a good result. Thank you very much. Have a safe trip.

[@TheDCCGuy]

Many thanks

[@TheEMD710]

This is exactly what I am looking for... Simple and easy to use.... I love all the cool stuff out there but it is very confusing... Thanks again Larry! Well done 👍

[@TheDCCGuy]

Glad it was helpful!

[@RootServerAdministrator]

Gramps makes the best model railroad tutorials.

[@christopherdavis5544]

Interesting as always, Larry. I hope you enjoy your visit to the UK. You will need all day to see everything at the Warley show, or perhaps both days. Will say hello if I see you.

[@rl7881]

Larry, re your reply to my comment: There is a lot of dedicated terminology used in electrical/electronic work, as indeed most other fields, and it’s easy to become a bit ‘hung up’ on assuming that everyone knows exactly what you’re talking about. You’re pitching your videos to enthusiasts of varying levels of understanding, but rest assured you’ve got it just right.

[@KJ7JHN]

I wish there were more videos like this. Thank you!

[@georgehussey1237]

Hi. Thank you for all this information. I have tried to get the PCBs here in the UK and quotes I have had varied from £250 to £480.00. for 30 boards. The chinese company wanted £50+ for postage for 5 boards. So I came up with a "Vero-Board" solution that cost very little to produce. I have built my first one and now trying to see how to incoperate it into my layout. Thanks again.

[@TheDCCGuy]

Sorry to hear that postage is so high to the UK. Did they base the shipping on using a carrier like DHL or their own cheap mail packet? The DHL rate is pretty expensive and it what their shipping quote defaults to so you have to select the cheapest option. I still got mine in only a little over a week.

[@zr1rob]

I built 14 of these for 7 blocks of both directions. I can show the way I interconnected them using RJ45 ethernet cable, but I don't know where to upload the schematic. All in all, the system is inexpensive, it does approach lighting perfectly, and it's very simple and quick to build. 2 Thumbs UP.

[@TheDCCGuy]

So glad to hear it worked out so well for you. You can email me your diagram as an attachment to ljpuckett at icloud dot com .

[@bernicemeade3232]

I'm loving it how you build them ABS signal circuits you're the best

[@scentgrasslakerailway]

Excellent, thanks too for sharing the design!

[@stevestallings8766]

Larry, I just downloaded your gerber file and placed an order with JLCPCB for 50 of these boards. It was an easy process that only cost $12.50 for the boards and $5.53 for shipping. About $18 total for 50 boards delivered is about 36 cents each - fantastic. I'll use your parts list (with the 750ohm R1 adjustment) to buy my components. Now I just have to get my NCE BD20 occupancy detectors and ABS signals.

[@user-bh1zz6wy6o]

Hi Steve, can you tell me how you downloaded the Gerber file please? I've asked Larry as well, and am waiting for an answer

[@peterjhillier7659]

Thanks Larry, I am ever amazed at your abilities, fantastic, really appreciate you sharing and making all your Ingenuity. Best Wishes, keep safe.

[@56NeilWatson]

Larry, hope to say hi to you at Warley. I didn't realise it was on next week and it's only just over an hours run for me.

[@marcellinden7305]

Awesome work Larry....I just wish you posted the PCB file you used to get the boards made so I could get my own boards made. You have a simple solution to a headache of a problem

[@TheDCCGuy]

I provided the link to the site where you can download them. Wordpress will not allow me to upload that file format to my freebie website.

[@johncloar1692]

Thanks Larry I will build some of these.

[@scentgrasslakerailway]

Larry, I have redrawn the pencil sketch (shown starting at 21:45 in this video and on your blog (both versions) in colour using Illustrator and saved as a pdf. If you want them to freely use and distribute please let me know... -Don

[@thomasgrassi8817]

Hi Larry very interesting did not know you can get circuit board printed up for you I had many ideas in the past but let them go because I did not know you could do that glad to know maybe I can recall some of those

[@TheDCCGuy]

I didn’t know until about a month ago either, which is why it took me 20 years to get it done! Once I watched the tutorial video it took me about 2 days to get the circuit file created and the boards ordered. Granted it was a very simple circuit but there are tons of them on the internet that could be created just as easily.

[@mikedowell8978]

Thank you

[@Electronzap]

When I saw the title, I thought you made anti lock brakes for your train lol. Cool circuit though, I subscribed. I should get into model railroading.

[@elsdp-4560]

Thank you for sharing.Great information.👍👀

[@peterkrause5187]

Super! Thanks Larry. Appreciated

[@rl7881]

Regarding the comment from Tron, and hoping not to cause offence: I have worked in the field of Industrial Process Control Instrumentation for 45-years, and the term ‘Ground’ for an electrical circuit should only be used when that circuit is connected directly to the general mass of earth, e.g. a protective earth (PE) circuit or signal screen circuit. For dc derived supplies such as cells/batteries or electrical ac to dc power supplies, the correct term for a negative potential conductor is notated as ‘0V’, pronounced zero volts or nought volts. It may also just be notated as ‘-‘, or minus, but is still referred to as nought or zero volts. Hope this is of help.

[@TheDCCGuy]

I always debate saying 12V- instead of ground (GND) but novices tend to be confused moreby saying ground instead of referring to the 12V- connection from the 12VDC power supply. EEs will argue both sides as another commentor just did.

[@bigchoo608]

Hi Larry, great stuff, enjoy all your videos. This ABS series sounds exactly like what I am after. I know you have given us websites and such - but is there not just a simple way to order a bunch of boards from the Chinese company - I am not sure about the gerber file upload - can it not be as simple as tell them reference order# blah blah - for detector logic 2 - give me a quote for x amount, etc.?

[@TheDCCGuy]

I don’t think they are set up to make things easy! They seem to be more focused on the advanced electronics hobbyists and circuit designers who deal with this stuff on a regular basis. You just need to bite the bullet and try to muddle through. Plus they do have customer service techs online all the time to answer your questions, which I did on more than one occasion. Their appear regularly in little popup boxes to ask i if they can help you.

[@user-bh1zz6wy6o]

Hi Larry, what is the name of your Gerber file for the ABS Signal circuit please? I'm new on the Easy EDA site, and need some help getting around it, thanks

[@TheDCCGuy]

You create the Gerber file using the project. Did you watch the video I provided a linked to on how to do this?

[@richardanderson8237]

Larry, I wanted to insert a circuit for dealing with frog polarity of turnouts within the blocks. Any suggestions?

[@TheDCCGuy]

No.

[@tronmcconnell4465]

As an electrical engineer, I found your use of the phrases "minus 12" or "minus 12 volts", when you actually meant "ground side" of your layout's12 volt supply, to be confusing, and, for people new to the hobby of model railroading, perhaps a little misleading. When discussing electrical issues, I would encourage the use of a more precise choice of terminology.

[@TheDCCGuy]

I always debate saying 12V- instead of ground (GND) but novices tend to be confused more by saying ground instead of referring to the 12V- connection from the 12VDC power supply. Another commentor just argued against saying ground as it implies a true earth connection. So I just try to fully describe the electrical connections as best as possible.

[@theknickerbocker5808]

Excellent video, Larry. With the use of this system, how long could your blocks be? Hate to think the signal system would upgrade to Approach while a train was still in the block.

[@TheDCCGuy]

In the video I showed a diagram pointing out the blocks should be about as long as your longest train plus about 15%.

[@theknickerbocker5808]

@Model Railroading Thanks, would you also recommend adding resistance wheel sets to your rolling stock for better detection?

[@TheDCCGuy]

I don’t add them to all rolling stock, just cabooses and unlit passenger cars. Once I am operating multiple trains I likely will add them to a small percentage as needed. I will do a video on that aspect of current based detection.

[@iandogokot]

Sorry, but i cant seem to find the document when i search up the circuit. Could you paste the link? Thank you, Ian.

[@TheDCCGuy]

Did you red the description, I put the updated info on there last week?

[@iandogokot]

@@TheDCCGuyyes, I did. I copied and pasted it directly into the platform. Any ideas? Thank you for your response.

[@TheDCCGuy]

I just tested it and the link works. Try searching for just “detector logic 2” and look under Modules.

[@iandogokot]

@@TheDCCGuy Okay, thank you very much sir. Have a good rest of your evening. Sorry for the inconvenience.

[@zr1rob]

Larry: Thanks for this. I've built it and am testing, with mixed results. What should the unused inputs at the beginning and end of the chain get? Eastbound YI and Westbound GI in particular at the right side of the chain and EB GI and WB YI at the left. Should I float, ground them or set them to +V? Also, why did you go with a larger R1? Since I'm using 5V instead of 12V as you did, should I try a larger value for R1 as you did? I figure it should be about 240ohm, based on the ratio you used.

[@TheDCCGuy]

Yes, you do need to use the 5V component list but remember the list in the original article is reversed. I spoke to Jeff Sherb about the issue I had and he told me he had never experienced the need to change the value of R1 so it could be I got a batch of transistors out of spec. At any rate all I can advise is try it with one value and see if it is stable but be ready to test with the alternate value which is what I did with the hand built ones I showed.

[@zr1rob]

@@TheDCCGuy I appreciate the response, and I did use a 220 in place of the 150 called for, the result is no change, so I guess the 150 originally called for is fine. The system works great going East (left to right on the diagram at video time 22.22). West doesn't light up at the rightmost block. Should there be some inputs to that block for trains entering the system going West?

[@TheDCCGuy]

Yes if you look closely at that diagram it shows the connection between the detector and the boards (shown in basic logic form) on both sides of the single track. I use the normally green on configuration which only requires the yellow wires be connected between boards. For advance loghting you would also need to add the green wires as shown in the original article and my hand drawn diagram.

[@jaypanditharatne9198]

Hi Larry, Excellent demo!, I used a ‘simplified’ BD20 unit as described by JT Chamberlain of A-Train Systems, with your ABS simplified circuit but no avail! Are you or will you be able to have a look at the said (of if I send you the circuit of the same for you to have a look at) as I have purchased some of ABS circuit boards and like to make full use of them. Any advice/help will be greatly appreciated, With Kind Regards Jay, ‘Down Under’ Melbourne

[@TheDCCGuy]

Did you bench test the circuit boards as I showed in the video? If they work as mine did then it is not the ABS logic board and instead must be the detector. If the circuit board does not work in a bench test then you need to recheck your soldering and make sure all components are oriented correctly. I find that about 99% of all electrical problems are due to wiring/soldering issues.

[@danshobbies13]

I want to know what you do with all these circuit boards. How do you mount them to the layout underneath. Just hot glue, tape? If all boards had holes for screws, then fine. But many don’t

[@TheDCCGuy]

Double sided foam tape or adhesive backed Velcro. You could also drill a mounting hole in the edge

[@kargandarr]

I have looked on your wordpress website and cannot find any of the files or diagrams on there. Not for this circuit, anyway.

[@TheDCCGuy]

I just looked and it’s the third one down on the page.

[@Sparticus]

I cannot locate the file. I searched for "detector logic 2" and it returned over 1400 results, none were correct. Is there another way to obtain the file?

[@TheDCCGuy]

They apparently reworked their web interface. When the search results come up there is a heading line listing various directories. Click on the “modules” selection and they are right there listed as PCB_Detector logic 2.

[@jamesbarton2507]

Larry, could you explain how to generate a Gerber file from the Easy EDA site and, then, how to copy it so it can be sent to jlc, please? I registered at EDA but could not find how to generate the Gerber file. Thank you.

[@TheDCCGuy]

Once you have found my detector logic files and opened them in EastEDA or generated your own circuit board diagram look up at the top menu and under Files there is an option to creat a Gerber file. You can also just go to Fabrication and at the bottom submit a PCB order. They usually have tech support folks who appear in popups to answer any questions you have. Be careful selecting a shipping method.The epacket is cheapest a d actually comes much faster than they project. The UPS and DHL options can run into money.

[@joeahearn4413]

Great videos on ABS and detectors. Can you give the title for the Gerber file in EasyEDA? I am having trouble searching for it or your user ID.

[@TheDCCGuy]

As usual its in the description along with other useful information.

[@joeahearn4413]

@@TheDCCGuy OK, read - then reread 🙃 - and follow directions... Found them, thanks

[@richardanderson8237]

Larry, I've been studying your video for a week now and have ordered the components for the boards. Im working through the Easyeda program and have the transistors and diodes on sheet 1 of my file. I couldn't locate your gerber file you mentioned. I've never tried this before so could you direct me to the gerber file?

[@TheDCCGuy]

You create the Gerber file using the project. Did you watch the video I provided a linked to on how to do this?

[@richardanderson8237]

yes I am. I don't know how to download your file that you offered.@@TheDCCGuy

[@richardanderson8237]

Larry, I started to get back into model railroading a year ago during my retirement. After watching several KZbin videos, especially yours, I became confident that I could create my first DC layout in the attic loft. Its 16x5' in HO. Your shared insights gave me many projects I was confident I could accomplish. While I'm doing projects I can listen to scriptures these past months. When I have problems, I ask God for directions and he directs me to seek your videos first and study your techniques. Thank You for your insights!

[@richardanderson8237]

Found the gerber file, thanks

[@richardanderson8237]

Had to copy and paste your opened file into mine then I could create a Gerber file and order PCBs. Several Tutorials on KZbin were helpful to learn the program pentameters. It is helpful to know computer programs and how to navigate them.

[@marcio_silva2504]

Good evening Lerry. My name is Marcio and I live in Brazil. Here we are very deficient in signs on the models. This method of yours is perfect and I wanted to reproduce it in my model. I would like to know if you could send me the model file of this board that you made in china. I thought the price was very good. thank you very much in advance.

[@markmatteo2417]

Could this be altered to use optical detectors?

[@TheDCCGuy]

Yes, any type of detector that supplies a 12V- (GND) connection to the detect in screw terminal should work. However, an optical detector will only activate the signal as long as there is something blocking the optical path. The type I used detects a loco or detectable piece of rolling stock anywhere in the block. You would need some kind of “latching” circuit with an optical detector.

[@markmatteo2417]

@@TheDCCGuy but with current detection I need to install insulated rail joiners and crest blocks, no?

[@TheDCCGuy]

Yes, you would need to gap the rails at block boundaries, but that can be done with a Dremel cutoff disk or razor saw. If you don’t want to see the gaps you can insert styrene sheet, glue it in place, and then cut to the rail profile with a knife. I usually just leave them open to serve as expansion/contraction joints.

[@kenkiesal1917]

Will this circuit work with the Digitrax BD4N?

[@TheDCCGuy]

In looking over their documentation it appears their detect out is positive [+] whereas this circuit requires a negative a (-) detect signal. I have not used these so you will need to confirm this with Digitrax tech support.

[@TheSonofruss]

I would have added a non connected hole for a mounting point and added stand offs

[@TheDCCGuy]

I just use commercial strength velcro to attach them to the underside of the layout. Faster and easier than a screw.

[@kenr86]

I didn't see an earth / ground / 0 volt connection on the circuit....

[@TheDCCGuy]

The earth is supplied through the detector connection or directly via the 12V- connection should you use that option. I always debate saying 12V- instead of ground (GND) but novices tend to be confused more by saying ground instead of referring to the 12V- connection from the 12VDC power supply.

[@TheEMD710]

Cant seem to find that ter-404 on all electronics??

[@TheDCCGuy]

As I said in the download they may be out of one configuration or the other from time to time. When I ordered they had the 4 but not the 5. So I bought the 6 pos and cut it down to 5 with my Dremel cutting disk. Also you may find them elsewhere such as Jameco.

[@TheEMD710]

I didn't pay attention.... Sorry for that... My bad . Makes sense.. easy enough to do. Thanks again Larry!

[@shanestrains4724]

How do I find the Gerber file to download?

[@TheDCCGuy]

One option with EasyEDA is to generate a Gerber file and download it.

[@shanestrains4724]

Ah. I was trying to do it from my mobile which was the problem. I fired up the laptop and all is good I ordered 20. I'm probably not going to need them all and for the price I can give away what I have left over. Cost was just over 17 bucks CAD and I used ground shipping (10 to 18 days). Thanks again Larry. 👍

[@kenkiesal1917]

I just tried to order 20 PCB and they wanted $50.83 to ship to Canada

[@TheDCCGuy]

Strange, were there various shipping options? I had mine shipped by their standard epacket and it arrived in a week or two. They also offer 3-5 day special delivery services through UPS and DHL that are more expensive and I bet that it what you selected. Did you download the Gerber zip file to your computer? If so you can submit that to an online PCB service in the US or Canada.

[@tjfedor9575]

@@TheDCCGuy I’m trying to locate the Gerber file. Can you share a hyper link to the file?

[@TheEMD710]

We need to be neighbors......