Ok, my apologies. I was only trying to help those who want an operating signal system on their layouts. It was not my intent to confuse anyone.
It is a building block system, built one at a time. Like looking at a bundle of wires can be very confusing. How could I ever do that? If you run one wire at a time, it is not longer confusing.
I have heard many model railers voice that they would love to have an operating signal system on their layouts. I was going to show how to construct the boards, build the signals, commercial ones are way to expensive if you haven't noticed. :)
This was and is a very inexpensive system to build and it is really satisfying to see your trains running up/down the line, with the signals doing their thing.
Perhaps I was overthinking it all.
So, I removed the thread. Perhaps, when I am able to explain it in easier terms, I will retry. Till then, I removed the thread.
Again, it was not my intent to confuse.
Dave
Seattle
Dave,
When it comes to electrical stuff, some of us are easily confused.....not your fault. You are right, many of us would like a functioning signal system, but it does get complicated.
I look forward to your future attempt.....simple is good for those of us that are a little thick headed. ::)
It's unfortunate you removed the thread. Don't take some discouraging comments as reflecting the "silent majority" of those of us who read many more posts than they comment on.
dave
I wil be redoing the thread. Just going to try and approach it from another direction. If I can't, then I may just assume that whoever is reading it, knows what's going on.
Dave
Seattle
Dave,
I enjoyed reading what you were doing and I didn't mean to offend you and I certainly wasn't offended. I'm very weak when it comes to what you and Bob were talking about.
I'm using the Digitrax signaling system and I'm confused over that as well. Like you said one wire at a time.
Tom ;D
Quote from: deemery on January 14, 2016, 10:28:17 AM
It's unfortunate you removed the thread. Don't take some discouraging comments as reflecting the "silent majority" of those of us who read many more posts than they comment on.
dave
Dave,
It wasn't my intent to discourage Dave and his thread. I just made a comment that some of us may be confused but it didn't mean we weren't interested.
Tom ;D
I was looking forward to following this thread as I also was wanting a signaling system for my "eventual" layout. I am a novice to all of this and completely dumb as a doorknob when it comes to electronics. BUT, if I can see with my eyes what needs to be done, then I CAN do it....
I was and am not discouraged. Nor am I offended. I have never taught electronics, though I have studied it extensively. With the comments that were coming in,
it appeared I needed to back off, regroup and try again.
It really is not as hard as it looks. But, I believe my explanation of it, was making it look and feel difficult.
When something is easy for a person, that has a tendency to enter into the explanation. It makes it very difficult for someone, who doesn't know anything about it.
So, it is coming back. I am just regrouping and sorting it all out.
Dave
Seattle
Thank you Dave , I hope you can do it again in Electronics for Dummies style , but I also know how it is to teach something that is very basic and natural to yourself. I have never been able to teach English to Dutch people for the simple fact that I am not capable of explaining things that are logical and natural to me.
Quote from: Janbouli on January 14, 2016, 05:42:09 PM
Thank you Dave , I hope you can do it again in Electronics for Dummies style , but I also know how it is to teach something that is very basic and natural to yourself. I have never been able to teach English to Dutch people for the simple fact that I am not capable of explaining things that are logical and natural to me.
I once heard the Dutch Language described as a cross between English, German, and a very bad head cold :-) ("logical" is not a term I'd apply to English grammar, let alone English spelling.)
dave
I was very interested. I have a degree in Electronic Control Theory and spent 13 years in the design of specialized computer controls, but that was 30 years ago and I found it refreshing to see what you had done. As I said before it brought back memories and interest on how you were or had solved the train signal control issue. With advances in electronics and PLAs I have it on my list of things to renew in the next few years. Give us details of what you did, dummying down does not benefit anyone and for the ones who did not understand, they are unlikely to ever implement. The ones with the desire should get all the benefits in your thread.
Ok, Take Two CLACK!
I am in fact about 1/4 done signaling my layout using one 4PDT relay per power turnout, with a mix of Chubb DCODs and Olin's Depot OC-1s, using Circuitron SD-3s to drive Oregon Rail Supply bipolar LED searchlights. I've got a thread going on RR-line. So I'm curious about how you'd do it.
James
Sorry it has taken me so long to respond. I kept trying but it seems the only coming up was facebook. No way to reply. Finally found the reason.
Would I be assuming too much to believe you are using the relays to route your signal indications to Normal and Reverse?
The system I built uses digital logic to do this function. The only mechanical connection to make it do the same thing as relays, is a mini relay (dpdt) to drive the logic either high or low.
The only thing the relay causes either a low (true) or high (false)...don't forget, I am talking about negative logic here...input at either one of two gates inputs.
It is not used to route the signal indications.
Dave
Seattle
This pic, crude as it is, shows the shorthand for a left hand turnout.
(https://modelersforum.com/gallery/206-260116233521-109141836.jpeg)
This pic shows the gate logic in the 74LS32 TTL and the gate logic in the 74LS08, that are on each turnout signal routing board. With the inputs and outputs labeled the same as on the shorthand.
The original design was by James Kyle. These turnout logic boards, gave me some real trouble in the beginning. The original design was mispinned and labeled. Using the same chips as the original, I had to redesign it. One pin off and the whole thing is useless. It had outputs as inputs and inputs as outputs...
(https://modelersforum.com/gallery/206-260116233520-108951769.jpeg)
Thinking vertically is hard enough, but normal. Horizontal thinking (negative logic), is another animal entirely. But that is exactly what makes this system work so well.
Dave
Seattle
Dave, I am using the relay to follow the state of the turnout. That way I only need one normally open contact on the switch machine or whatever is running it.
I'm using ground as the 'active' level on my 'occupied' circuits because that's what the DCOD generates and the SD-3 wants as input. So if a turnout is against a route, the 'occupied' feed to the SD-3 operating the corresponding signal is grounded. I use diodes when I want to keep a turnout's position from affecting signals which don't care about it, like those governing facing point movements.
In most cases I only need four circuits along each block, because the Stop (Red) terminal of a given signal driver is connected to the Caution (Yellow) aspect of the signal to the rear. I do have to switch the Caution lead with turnout position for bi-directional double track, but my prototype and era didn't have much Rule 261 territory - my layout only has four blocks of bi-directional double track.
This link brings you into the middle of my build. The circuit diagrams are for the Rule 251 (current of traffic Automatic Block) section I have mostly finished.
( http://www.railroad-line.com/forum/topic.asp?TOPIC_ID=45342&whichpage=3 link was for old Snitz RR-Line )
https://railroad-line.com/node/33232
RMC has Part 3 of a series on signalling by Dr Bruce Chubb in the latest (Feb 16) issue. There's also a favorable review of an interesting book being self-published through Amazon.com, "DIY Advanced Model Railroad Signaling Electronics: Sensors, Interactivity, Track Control"
dave
Ok everybody...here are three blocks on a breadboard to show you what I built for a signal system many moons ago. Back when the twin-t was king. The only difference, instead of my input being from a relay, I used opto-isolators to activate the signals. TTL was still a youngster.
Now, I have the DCCBOD type detectors. Which I built also. None shown here though. Just using a piece of wire to drive the Re input.
What you see here are as I stated, no driving transistors, no dropping resistors. Very inexpensive! Each signal head, uses a 74LS00 quad two input NAND chip.
All the circuitry is inside the chip, with the exception of course, to interconnect the inputs and outputs between the pins and in and out from the board.
The Re is low, or ground when the signal is red. This drives the signal behind it to yellow. East bound and westbound heads all have their own board.
Here in these photos, you can see the progression. Granted, it is only three blocks, but you should get the idea.
Each board costs around $1.50. Even a little less if you set up an assembly line and not try to only cut one board at a time.
It is a building block system with four components. Detector, signal head board, turnout control board and crossing board. The latter is not really used that much, but just in case you ever need one!
I will be putting together a couple of the turnout control boards and integrating them for you and show them working here in the forum.
This system is not more difficult that putting together snap track...one section at a time.
I do apologize for the brighness of the LED's and the little blur. I do not have a very professional camera. My tripod broke so it's handheld. Anyhow...
I used this system for 9 years and it operated flawlessly. Not a single LED burned out in all that time. The boards were never in need of repair or replacement!
This is a pic the chips used and the led's. The wiring of course could be put on those little pro boards and hardwired just like you see here, but I make my own printed circuit boards with a laser printer.
The bent orange wire represents the detector being activated. It is just being used directly to drive the signals. As this thread progresses, I will show the detectors and all the interconnections that make this system work.
(https://modelersforum.com/gallery/206-020216195431-10915220.jpeg)
Here are three of the blocks showing none occupied...Green Board!!
(https://modelersforum.com/gallery/206-020216195431-10986224.jpeg)
Here the second block is occupied. These signals represent Eastbound. Westbound would be wired up the same. One chip missing, but just pretend. It would be green.
(https://modelersforum.com/gallery/206-020216195431-10987416.jpeg)
Here the top signal is showing occupied.
(https://modelersforum.com/gallery/206-020216195431-109881523.jpeg)
Dave
Seattle
Oops, this pic should have been the second above. It shows the first block occupied and the two blocks in front clear.
(https://modelersforum.com/gallery/206-020216205910-109891894.jpeg)
Dave
Seattle
Small note here. I removed the drawing showing the relay contacts for changing the interlocking for the turnouts. I drew a D.P.D.T relay showing Ground and -5V.
I will redraw. That was incorrect. It is actually, supposed to be a S.P.D.T relay. Center feed going to ground only. Then the contacts going to NOR or REV.
I will draw it again and put it in the thread.
Dave
Seattle
I'm curious, as I have applications for a bipolar LED driver which costs less than Circuitron's SD-3.
Is that a complete question James. Curious about? Maybe I am just getting old and it's going over my head. :D :D
I don't know much about Circuitron products. I do know a driver for two color LED's can be built rather inexpensively, (inexpensive being a relative term determined by who you purchase from), using a 555 timer. I have done that also.
This system will not drive bi-polar LED's. Just color position signals.
A detector can be built using a 555 timer with the pin 3 output driving bi-polar LED's. Pin 7 is open collector. It gives you two ways to use it. I believe Mr. Paisley has one on his web site. It is DCC only Transformer type Block occupancy detector (555 timer) It is rather compact and would not be that expensive to build. All the parts for everything he uses and for that matter, what I use for this, can be had at Nebraska Surplus for a really good price.
I pay .40 for each chip on the signal drivers. Not including the board or signal itself of course. As I stated, the cost of each signal board is about 1.50 per. That includes the board.
Three color position light is actually, my personal preference.
Dave
Seattle
I'm modeling the B&M's Eastern Route in an era when all mast and dwarf signals were searchlights. Oregon Rail Supply is the only supplier offering a style of ladders and platforms I can use to make relatively accurate mast searchlight signals. I've built my own dwarf signals: https://railroad-line.com/node/28096 (old link to Snitz RR-Line http://www.railroad-line.com/forum/topic.asp?TOPIC_ID=39866 )
I could use Mr. Paisley's circuit board and build it without the approach lighting parts, but my dwarf signals are built with red/yellow bipolar LEDs for two aspects. Something simpler would do the job, which is what I'm curious about.
James
Well, just before I started texting this, I went to your link and saw what you were doing. It blew my suggestion out the window! You seem to have the patience of Job! I see your dilemma. Very nice looking signal you got there sir!
Am I reading that your problem lies in the size of the LED? Not the electronics. As red/yellow led's are available in 3mm, it seems you want 1.8mm. That would put you closer to scale.
You have texted you can use R.Paisley's circuit, just leaving out the approach lighting aspect. Am I understanding correctily?
If so, have you considered piping the light into the signal with fibre optics? Not sure about the simpler part. Then you could use the 5mm Led for more light, driving it for just red/yellow. You could use a 3 lead red/green. Then it is just a matter of red on one lead. Yellow if you drive both leads.
If I am still not understanding, exercise a little more patience and forgive me. My hard drive is full. Too many cookies up there. ;D ;D :o
Dave
Seattle
Thanks, but the styrene dwarfs actually go together fairly fast. I haven't yet found the patience to work with surface mount LEDs. And the 1.8 mm and 1.6 mm LEDs are too easy to damage when I try to reduce the size of their rectangular bodies to fit in commercial head castings. Years ago I lit one of the Century cast metal dwarf signals with fiber optics, but the result was not bright enough. So it's 3MM diameter bi-polar for the time being.
I have 8 locations where a Red/Yellow bi-polar LED gives the two aspects I need. Right now I'm driving them with a transfer contact on the turnout relay.
I would prefer to drive them electronically. The ideal circuit would have one input. Float is normal, ground reverses the polarity to the LED. It would be cheaper than Mr. Paisley's 556 driver. If it was more compact, even better.
Now that I have shown you pics of three blocks working. I will continue on with schematics. As was said, some of you may not understand it, but there are many who do.
I will try not get geeky on you, so ask questions. That's the only way to knowledge!
The chips that are used in this system, are the 7400 series TTL. When I first built this system back in the late 70's, TTl was still not that old. For those of you who do not know what TTL stands for...Transistor, Transistor, Logic.
Today, we have at our disposal, 74LS00 chips. Same circuitry, just greatly improved as a product. I pay .40 cents apiece for these little wonders of electronics wizardry.
Each signal head has one chip mounted on a small PCB. The signal driver board has on it, the 74LS00 Quad two input NAND
The internal circuitry is not important to build this system, it is too complicated. So we use shorthand, or symbols.
This shows the 4 individual NAND gate symbols, inside the chip.
(https://modelersforum.com/gallery/206-140116153213-106881682.jpeg)
Pin 1 is the orientation pin. Pin 7 is the gnd and pin 14 is +5VDC.
You need to have a 5 volt regulated power supply. I have a 5 volt, 4 amp dual regulated power supply. Though you do not use the negative voltage.
This system uses reverse logic for it to work. Normal usage uses positive logic. High input means true or 1. Low input means false or 0. I use Low input means true or 1. High input means false or 0.
This is how I use the NAND circuitry, to make a signal.
(https://modelersforum.com/gallery/206-130116205441-106791877.jpeg)
The pin layouts, are very important to adhere to. Do not deviate from this pin diagram schematic. You might notice I do not have pin 7 or 14 on the drawing. This will show up in a later posting.
Also note, that the LED's are common anode. These are connected to the mast of the signal itself. This is driven by pin 8 of the chip.
Coming off the board, there are only two inputs (Re and Ye) and four (kg, ky, kr)outputs. Then it has the voltage and gnd.
This is one complete signal driver board. There is one for every signal. Eastbound and Westbound.
The Re is Red enable input is actually, driven from gnd through the detector, when the block is occupied. Yo is Yellow out to the previous board. Ye is coming from the board in front and drives the yellow LED when the signal in front is Red, or occupied.
You may also notice, that pins 9 and 10 are tied together and grounded. This is for NORMAL lighting. Or the signals are on all the time.
Notice the dashed line going to Ge. This is for making the signals APPROACH lighted. Or, the signals come on only when the train enters the block behind it. Then it will either light up Green, Yellow, or Red.
I will show how to connect this up later, if you prefer APPROACH over NORMAL.
Here is one signal head circuitry hardwired on my breadboard.
(https://modelersforum.com/gallery/206-040216193051-109921209.jpeg)
Dave
Seattle
While I am waiting for the chips, led's, pcb material, etc., I thought I would go ahead and start up building some signals.
Today, I worked on a head. Now these signals I am constructing are in 'O' scale. I know most of you work in 'HO', but there could be some ideas here that you can glean.
The base for the head is a PCB that the led's are soldered into. I made the traces by hand with rub on's for the leads. The PCB is 13/16" x 13/64. This signal system is common anode. So the small strip of copper running from the top to the bottom, is where the anodes are soldered. The opposite side, is done with small, individual pads with a small tab just below the led lead. This small tab is where the wire will be soldered. It should make for a very clean and neat little package when finished. Shouldn't have big globs of solder. At least that's the plan.
(https://modelersforum.com/gallery/206-100216201300-112781208.jpeg)
This makes the actual support for all the LED's, the wiring and the signal target.
The target is cut from .20mm brass shim stock. The holes are drilled using a 5/32" bit, then cleaned up with a jewelers file. The target is 61/64" x 15/32"
The prototype target is 57" x 34".
(https://modelersforum.com/gallery/206-100216201300-112772212.jpeg)
The LED's are 3mm.
(https://modelersforum.com/gallery/206-100216201300-112761570.jpeg)
(https://modelersforum.com/gallery/206-100216201300-112751821.jpeg)
The hoods can be made from brass or aluminum 5/32" tubing and are 5/16" in depth or length.
(https://modelersforum.com/gallery/206-100216201127-112741330.jpeg)
The LED's are soldered into the board, then the hoods are placed with ACC. I have not done this yet as you can see in the pics.
(https://modelersforum.com/gallery/206-100216201127-112732436.jpeg)
Once that is done, the target is placed over the LED's and attached with ACC.
I don't have the wire yet. Like the check, it's in the mail!
(https://modelersforum.com/gallery/206-100216201127-112721150.jpeg)
(https://modelersforum.com/gallery/206-100216201127-1127134.jpeg)
(https://modelersforum.com/gallery/206-100216201127-1124589.jpeg)
When I get the wire, I will attach everything permanently, then I will make an enclosure from plastic channel stock. The wire will come out the bottom, of course.
The mast will have a hole for the wires to go into and down.
I will show all this once I get the materials I have ordered.
Well, it's a start!!
Dave
Seattle
The signals look nice. I have been using (US) #30 Kynar wire off the rack at Radio Shack. If they aren't still in business around Seattle, there should be at least a few electronics hobby/experimenter stores on the lines of You Do It in Needham, MA.
Thank you James! I am using the Kynar wire also. Yes, Radio Shack is still in business. But, they are not what they used to be by far.
I get the Kynar at a local electronics supply house, but, they are very expensive. 20.00 a roll! I am looking for a cheaper outlet!
Red, Yellow, Green, Black. All the appropriate colors.
Dave
Seattle
Your supply house probably considers M$ and Boeing their main audience. Radio Shack lists 50' of 30 ga. Kynar for $5.49.
Thanks James for the info.
I have been in Radio Shack here, but they sell it in a 3 pack with red, green and black. That leaves yellow. After I texted to you, I went to Jameco, and they have 100' rolls of #30, in all the right colors They are charging 12.50 per roll. Not bad for the amount of wire you get. I am ordering it today.
Dave
Seattle
Did some more work on my first ever scratch built signal. I can already see there are some changes I need to make in the construction.
But learning is a rocky road sometimes. No pain, no gain... :o :o
Not much texting to do. Just add some pics.
(https://modelersforum.com/gallery/206-110216191527-11288675.jpeg)
(https://modelersforum.com/gallery/206-110216191439-112872173.jpeg)
(https://modelersforum.com/gallery/206-110216191439-1128612.jpeg)
(https://modelersforum.com/gallery/206-110216191439-112851194.jpeg)
(https://modelersforum.com/gallery/206-110216191439-11284390.jpeg)
(https://modelersforum.com/gallery/206-110216191439-112791081.jpeg)
Making the braces for the shield at the moment. Pretty much out of time today though. Almost bed time. 2:30 a.m. comes pretty early.
By the way, the model in the background, is a radio control model of a World War II American Destroyer. Fletcher class to be exact. She really runs very nicely.
Dave
Seattle
Dave,
Wonderful thread, very informative. I think the signals look great.
Tom ;D
Thanks Tom! I am doing my best to keep it simple. It is a struggle sometimes.
Put the signal on hold for a bit. It was just to fill in space till I got things going on the signal system again.
Here are pics of the PCB pattern. Granted, they are extremely oversize, but they can be used to make your own or, to use as a hardwire guide.
That is a lot of work for hardwiring though. But, if that's all you feel you can do, then by all means, go for it! I look at making my own PCB's, as just another part of the hobby and I find it very enjoyable.
This pic is just the circuits for the signal board IC. This is set up for Normal lighting.
(https://modelersforum.com/gallery/206-160216184856-114212378.jpeg)
You will notice, there is a slash mark below and between pins 7 and 8 of the IC. This is where the trace would be cut if one was to go with approach lighting. Later on all that though.
This pic is showing the component and pad connections.
Re.....Red enable. From the detector board
Rc.....Red cathode. To the red led in the signal head
Yo.....Yellow out. To Ye on the previous board.
Ye.....Yellow enable. From the Yo on the board before.
Yc.....Yellow cathode. To the yellow led on the signal head.
C......5v common or ground on pwr supply.
Ge....Green enable. Used only if using approach lighting.
Mt....Mast connection or common anode.
Gc....Green cathode. To the green led on the signal head.
5v....+5v. connection on pwr supply.
(https://modelersforum.com/gallery/206-160216184856-11422133.jpeg)
I am preparing pictures and drawings of the interconnections for the signals as well as for the turnouts.
If there are any questions or comments, please feel free to ask or make them.
Dave
Seattle
The first breadboard demo you showed seemed to be driving bi-polar (2-lead, 2-color) LEDs. But your signal uses 3 separate LEDs and the PCB you show today has 3 outputs (I know there are 3-color LEDs with 4 leads). Do you plan to do anything further with bi-polar LEDs and searchlight signals?
Thanks for the drop in and inquiry James.
The Breadboard shows three led's per head. The camera made it appear that there was just one. The brightness of the led colors ran together. I didn't use a filter. But, I assure you, it is three color position light. There are no bi-polar led's in this circuit.
I suppose, once this system is finished, I could give searchlight signals a go. I just don't think I could really improve or do much different than what others have done. I have always been a large fan of position light.
A lot has been done, as far as circuitry for searchlight is concerned. Rob Paisley does a pretty good job of it. I really like this system, because it is very inexpensive and it uses a minimum of components.
Dave
Seattle
Little extra note here. Did a lot of work on the signal today. Here are some pics of where its at. Again, this is my first time at building one of these and its all brass construction.
(https://modelersforum.com/gallery/206-170216192056-114441134.jpeg)
(https://modelersforum.com/gallery/206-170216192056-114431139.jpeg)
(https://modelersforum.com/gallery/206-170216192055-114402264.jpeg)
(https://modelersforum.com/gallery/206-170216192056-114411301.jpeg)
(https://modelersforum.com/gallery/206-170216192056-114421218.jpeg)
It is being driven by the signal system on the breadboard.
Just 30 more to go! Once this one is done, the rest should not take as long to build. This is the prototype of course.
Some with double heads, for crossings. Some with four aspect for turnout interlocking. Then many just like this one.
Dave
Seattle
Perhaps I should have been building this prototype signal in another thread. But, it does go with the signal system. So here I go again.
I was not really planning anything today at all. Quite frankly, I was just going to be a couch potato, but I just could not keep my hands off this signal.
Here are some pics of the upper rails and platform.
(https://modelersforum.com/gallery/206-180216124121-114751447.jpeg)
(https://modelersforum.com/gallery/206-180216124038-114741094.jpeg)
Gotta do a little bending here and there and make small adjustments
(https://modelersforum.com/gallery/206-180216124038-114731342.jpeg)
(https://modelersforum.com/gallery/206-180216124038-114721786.jpeg)
Getting real close now to final fit.
(https://modelersforum.com/gallery/206-180216124037-114712330.jpeg)
(https://modelersforum.com/gallery/206-180216124037-1146976.jpeg)
(https://modelersforum.com/gallery/206-180216132400-11481639.jpeg)
(https://modelersforum.com/gallery/206-180216132400-114801490.jpeg)
(https://modelersforum.com/gallery/206-180216132400-11476141.jpeg)
The handrails are made from 1/64" brass rod.
The deck plate platform, is made from some brass etchings from Toms modelworks. They are actually, made for a model ship.
But what the heck, it works.
Well, there it is so far.
Dave
Seattle
Dave
I'm really enjoying the thread. Thanks for sharing this with us. The signals look great.
Dave...
This is really cool stuff
thanx
Bob
Thanks John and Bob, for the comments!
The are much appreciated.
When I get this prototype finished, I may do an sbs on construction.
Dave
Seattle
Apologies for the drawings that were here.
They really were not very clear. So I am redrawing them and will repost.
Dave
Seattle
Here are the redrawn connection diagrams for this system.
(https://modelersforum.com/gallery/206-250216091005-115852103.jpeg)
This is a continuation of the above photo. Left side of above photo, goes to the right side of this.
(https://modelersforum.com/gallery/206-250216091005-115771057.jpeg)
I have been asked what detectors I am using. Detectors, are pretty much your choice. You can build your own, which is what I do. I have or am using a detector designed by Rob Paisley.
Just remember, when there is no train in the block, it does not matter if the detector is powered from rail power or not. The logic for this system is negative logic. Low is true and high is false.
So, the signal system automatically goes low when unoccupied or... signal green. When the block is occupied, the system goes high or false... or, signal red. As DCC supplies power to the rails at all times, there is no need for a tickle voltage to run the system through the detector.
Having said all this, I am however, using a detector, that takes its power from the DCC booster system. There is a voltage drop with this detector of about 2volts, because of the diodes. It does cause a higher starting voltage of your trains and they will stop before your throttle is all the way off. This causes no issues for me at all. If it bothers you, he has a transformer style detector on his site also.
He has many useful circuits here:
http://home.cogeco.ca/~rpaisley4/DccBodXfmr.html
(https://modelersforum.com/gallery/206-250216094944-115862319.gif)
The opto-isolator on the output of the detector, is what runs the signal system. 5v gnd is connected to E. The output Re, is connected to D.
I have also made the PCB layout for this detector. Which I will post later.
Dave
Seattle
Hey y'all
Today, I started working on a turnout interlock signal. This is a regular signal with a lower, single target and lamp. (LED)
When the turnout is reversed, this lower signal will go yellow, while the upper signal will be green. When the loco enters the passing siding, the upper signal will go red.
This means that the approach normal signal will be red also.
So, the engineer has an absolute, but proceed with caution be prepared to stop. The placement of the yellow is always for turnouts only.
He knows he is being put on the siding.
Here is where the lower signal will be placed. If on the right hand of the mast, it is a righthand turnout. Left side, left hand turnout.
My railroads choice.
(https://modelersforum.com/gallery/206-020316095446-117831844.jpeg)
The LED's with their rounded face, does not look like a real lense. So, I file the top of the LED flat. IMHO, it looks more realistic.
(https://modelersforum.com/gallery/206-020316095446-117851357.jpeg)
Here it is with the hood placed, (still needs final filing and fitting). Also the shield. You will notice that the shield has been flattened on two sides. I preferred this look over the fully rounded shield. A matter of my perspective.
(https://modelersforum.com/gallery/206-020316095446-11786792.jpeg)
I will also be making grade crossing interlocking signals. These will have taller masts and one upper and one lower three color position light heads. There are four per grade crossing as per rules.
These show aspect for the crossing block and the next block beyond. These can show green over green. Green over yellow. Yellow over yellow. Red over red. Yellow over red. Red over yellow....hmmm.
Dave
Seattle
This probably doesn't apply to all LEDs, but I filed a 'diffused' T-1 LED flat on the front and lost most of the 'diffused' effect - the point of light from the silicon die was much more pronounced and the beam less focused. How important this is probably varies with situation and layout owner.
Yes, you are right on the filing an LED.
But, it sets them back into the hoods more. The light that is emitting, works fine for me. It was not really a recommendation for anyone, just my personal way.
Dave
Seattle
Today, I finished a turnout interlock signal. One of several coming.
I have not been able to find any ladder stock for these signal masts. Peco makes them, but it seems no one in the U.S. carries them.
At least not what I have been able to find on the I-net or two local model railroad hobby stores.
Perhaps someone out there reading this, might know where I can get these here is the U.S.
So, I thought I would try my hand at etching my own. Well, I know now that I can do it! The pics on the bottom, show this first attempt.
It really did not turn out as I would have liked, but I know that the reason being is, I used brass stock that was too thick and it had to stay in the acid way to long!
My next attempt, I will use brass sheet that is much thinner. I used .20mm brass shim stock.
Next time, I will use .10mm shim stock. That may be way too thick also. Perhaps I should try the next one with .05mm shim stock. That certainly will not have to be in the acid very long.
(https://modelersforum.com/gallery/206-090316125805-119091461.jpeg)
(https://modelersforum.com/gallery/206-090316125805-11908555.jpeg)
Still needing a hood on the green aspect.
(https://modelersforum.com/gallery/206-090316125805-119071585.jpeg)
(https://modelersforum.com/gallery/206-090316125652-11906679.jpeg)
(https://modelersforum.com/gallery/206-090316125652-119051055.jpeg)
(https://modelersforum.com/gallery/206-090316125652-119041646.jpeg)
(https://modelersforum.com/gallery/206-090316125652-11903126.jpeg)
(https://modelersforum.com/gallery/206-090316125652-11877720.jpeg)
As you can see about midway up, the acid went right through the side rail. I also need to find a permanent marker that has a lot finer tip.
I discovered that making your own etchings, is not a difficult thing to do. I also learned that you better have the right thickness of brass or you will eat up what you are trying to make. I also learned, that brass etches slower than copper.
All things you might all already know.
Dave
Seattle
I have started showing too much signal. I need to get back to the actual ABS part. I have been working on some more drawings that I have been wanting to post, but making the signals got in the way.
I will catch up on these and begin posting actual signaling diagrams or schematics for you all to peruse.
Dave
Seattle
Making pcb', for some of you, may not be something you are interested in doing.
Today after work, I am stopping by my local R.S. and purchase some experiment boards. I will show how each board is to be wired and interconnected with these.
It is pricey to do it this way but, if you are not equipped or ready to make your own pcb's, the cost in the long run, kinda works out for you.
The size of theses boards are actually, close to the same size as the homemade PCb's.
Instead of sharing here the process of making your own boards, this may make all this more clear and easier to follow.
No insult intended for anyone's abilities mean here.
If you can make your own boards, let me know and I will share the needed info.
Dave
Seattle