Electrical
Simple Structure Lighting
25 September 2016 23:51
It’s been a REALLY long time since my last post, since I got caught up in several other things after I started this review. I also planned to do more real-world testing with the lighting system reviewed here. I haven’t found time for that either, but I kept procrastinating on posting hoping I’d find a spare weekend. I didn’t. So I’m going to post what I have, and I expect I’ll eventually do a follow-up when I’ve had a chance to light a couple of buildings.
Woodland Scenics came out with their Just Plug building lighting system a couple of years ago, and I’ve been meaning to take a look at it, and see how useful it would be ever since. On the surface, it appears to be a dead-simple plug-and-play method of lighting buildings that you can power off any low-voltage AC or DC supply, such as the AC accessory outputs on a DC power pack or a simple “wall wart” power adapter. And it is.
It’s not cheap. A pair of stick-on LED lights with wires sell for US$10, the basic hub goes for US$17 without lights, and the expansion unit for a similar cost, and they’ll happily sell you a 1 Amp power supply for US$20 (about three times what you’d pay from a good electronics shop). A large system, with two expansion hubs, eight light hubs, and 32 lights would cost about US$348, or US$10.88 per light (with power supply). You could build the same thing yourself for less than a tenth of the cost. Except for two things.
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Woodland Scenics came out with their Just Plug building lighting system a couple of years ago, and I’ve been meaning to take a look at it, and see how useful it would be ever since. On the surface, it appears to be a dead-simple plug-and-play method of lighting buildings that you can power off any low-voltage AC or DC supply, such as the AC accessory outputs on a DC power pack or a simple “wall wart” power adapter. And it is.
It’s not cheap. A pair of stick-on LED lights with wires sell for US$10, the basic hub goes for US$17 without lights, and the expansion unit for a similar cost, and they’ll happily sell you a 1 Amp power supply for US$20 (about three times what you’d pay from a good electronics shop). A large system, with two expansion hubs, eight light hubs, and 32 lights would cost about US$348, or US$10.88 per light (with power supply). You could build the same thing yourself for less than a tenth of the cost. Except for two things.
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Signals and Signaling with Arduino
28 March 2015 22:28
I’m going to vary from my normal focus on modeling Japanese railroads today to talk about signals and modeling them in a more general sense. Heck, who am I kidding, there haven’t been many posts on modeling Japanese railroads of late. But I digress from my digression. Back to the subject: signals.
If you want to cut to the chase: I’ve written an Arduino library for controlling lineside LED-based signals. It’s only part of a complete signaling system that I’m working on, and at present you’d have to do more work to make practical use of it. But the code is public and can be used independently of anything else I’m eventually going to create; skip down to the end for details.
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If you want to cut to the chase: I’ve written an Arduino library for controlling lineside LED-based signals. It’s only part of a complete signaling system that I’m working on, and at present you’d have to do more work to make practical use of it. But the code is public and can be used independently of anything else I’m eventually going to create; skip down to the end for details.
Read More...
More on Layout Lighting
07 September 2014 23:03
I’ve been thinking about a number of things related to the layout this month, but mostly about lighting the layout itself. The current layout is lit by a mix of my original track lighting system (using compact fluorescent bulbs) and the newer fluorescent tube valences.
That experience convinced me of the merits of fluorescent tube lighting. It also convinced me of the need to build the lighting valence as part of the benchwork, rather than trying to suspend it from an irregular ceiling. As you can see above, the heating ducts caused some difficulty in attaching the lighting units in this part of the basement.
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That experience convinced me of the merits of fluorescent tube lighting. It also convinced me of the need to build the lighting valence as part of the benchwork, rather than trying to suspend it from an irregular ceiling. As you can see above, the heating ducts caused some difficulty in attaching the lighting units in this part of the basement.
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Train Power - When DC is not Direct Current
23 February 2014 22:44
This is the second (or third if you count the previous diversion into history) in a continuing series of posts on powering model trains. The first installment covered some basics of DC motor design, and if you haven’t read it, it’s worth at least a skim before reading today’s post, since it provides a lot of background information (or read the DC Train Motors page, which has been updated considerably from the original material). Today we’ll get into how modern “DC” power packs aren’t really DC, and what aspects of DC motor behavior make that a good thing.
Most modern “DC” power packs don’t really put out DC in the sense of a fixed voltage for a given throttle position. The reason for this is that DC motors don’t really run very well at slow speeds. They work best at a fairly high rotational speed. In the early days hobbyists had to be content with models that went from “stop” to “rather quick” with no intermediate speed. This is often referred to as a “jack rabbit start”, and it’s hardly prototypical. Real locomotives weigh several hundred tons. Nothing that heavy accelerates quickly, and if it’s pulling a train that can weigh upwards of 10,000 tons it’s even slower to get up to speed.
Passenger trains (multiple unit type) tend to weigh less, and often have more and distributed power so they can accelerate faster. But there are limits to that, as passengers tend to object to being hurled backwards. And “weigh less” still means that a train will weigh 100 tons or more without passengers, and a full load of those can easily add 50 tons. That’s a lot to accelerate quickly.
I’ll get into the details below, but the short version is that modelers discovered that “pulsing”, or varying the power in a repeating manner, allowed a train to start more gently. This wasn’t without its problems, and various different approaches were tried over the years, although the earliest technique proved quite effective and continued in use for over twenty-five years. In fact many systems today use a technique known in the 1950s, but not considered “the best” at the time. It’s still a compromise, but a popular one. Today all but entry-level DC power packs produce pulsed power in some form, and it’s so commonplace that most don’t even mention it. There are exceptions, of course.
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Most modern “DC” power packs don’t really put out DC in the sense of a fixed voltage for a given throttle position. The reason for this is that DC motors don’t really run very well at slow speeds. They work best at a fairly high rotational speed. In the early days hobbyists had to be content with models that went from “stop” to “rather quick” with no intermediate speed. This is often referred to as a “jack rabbit start”, and it’s hardly prototypical. Real locomotives weigh several hundred tons. Nothing that heavy accelerates quickly, and if it’s pulling a train that can weigh upwards of 10,000 tons it’s even slower to get up to speed.
Passenger trains (multiple unit type) tend to weigh less, and often have more and distributed power so they can accelerate faster. But there are limits to that, as passengers tend to object to being hurled backwards. And “weigh less” still means that a train will weigh 100 tons or more without passengers, and a full load of those can easily add 50 tons. That’s a lot to accelerate quickly.
I’ll get into the details below, but the short version is that modelers discovered that “pulsing”, or varying the power in a repeating manner, allowed a train to start more gently. This wasn’t without its problems, and various different approaches were tried over the years, although the earliest technique proved quite effective and continued in use for over twenty-five years. In fact many systems today use a technique known in the 1950s, but not considered “the best” at the time. It’s still a compromise, but a popular one. Today all but entry-level DC power packs produce pulsed power in some form, and it’s so commonplace that most don’t even mention it. There are exceptions, of course.
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A Short History of Transistor Throttles
02 February 2014 01:41
My interest in the design of transistor-based DC throttles (aka Power Packs) for model railroading ended up causing me to pick up the DVD set of Model Railroader back issues (henceforth identified as MR). While US$200 seems like a lot, I think it was well worth it, if only to satisfy my curiosity. And it works out to less than US$0.30 per issue, so in a sense it’s a bargain. I also dug up a copy of Peter Thorne’s 1974 book Practical Electronic Projects for Model Railroaders (mine is the third edition of 1975), which has a number of throttle circuits, including one using an SCR. This book can go for rather high prices online, but I found mine at a train show last week for the cover price of US$3.50; quite the bargain.
Early-on electric model trains were run with car batteries (some early ones used AC motors with AC from a transformer instead), first apparently at 6 volts but by the 1930’s DC motors were apparently designed for 12 volts even before cars switched to the larger batteries, requiring two batteries placed in series (per MR August 1934 article on the use of DC power). DC at 12 volts was more than enough to run small motors, and early throttles were little more than a variable resistor (rheostat) to reduce voltage for slower speeds, and a Dual-Pole, Dual-Throw (DPDT) switch to reverse polarity for direction control. Often a “knife” switch would be used for the reverser, which could be left in a central “off” position to disconnect the throttle from the track.
But modelers weren’t very satisfied with these. DC didn’t allow for smooth low-speed operation, and “jackrabbit” starts with a minimum speed over 10 or even 20 scale miles per hour (16 - 32 kph) made for poor switching operations. Plus, modelers wanted to model the behavior of real trains, with simulated momentum and realistic braking action.
This led to designs for more sophisticated “throttles” and ever more complex designs as electronics technology improved. Some of the results did a fairly good job of replicating the real behavior of trains, right down to simulating the performance of air-brake systems similar to the one in the diagram at the top of this post. It’s possible some of this took place before the transistor was introduced; vacuum tubes could have been used for similar things. However, nobody appears to have published their experiences with these, so it seem likely that little or nothing was done until the transistor came along.
The development of the low-cost transistor in the late 1950’s made more complex throttles accessible to a hobbyist with a relatively minor amount of electronics skill and for a reasonable price, and the next decade was a time of rapid change, with evolution continuing into the 1970’s. By 1980, interests had shifted towards running multiple trains using command control systems (the precursors of DCC), although the roots of those went back further. And even in 1980 you could still buy rheostat throttles, although they were definitely behind the times by then. None of these technologies fully displaced the others. The transistor has in fact soldiered on into the era of digital controls, and you can still buy transistor throttles today that aren’t too different in principle from those designs of a half-century ago.
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Early-on electric model trains were run with car batteries (some early ones used AC motors with AC from a transformer instead), first apparently at 6 volts but by the 1930’s DC motors were apparently designed for 12 volts even before cars switched to the larger batteries, requiring two batteries placed in series (per MR August 1934 article on the use of DC power). DC at 12 volts was more than enough to run small motors, and early throttles were little more than a variable resistor (rheostat) to reduce voltage for slower speeds, and a Dual-Pole, Dual-Throw (DPDT) switch to reverse polarity for direction control. Often a “knife” switch would be used for the reverser, which could be left in a central “off” position to disconnect the throttle from the track.
But modelers weren’t very satisfied with these. DC didn’t allow for smooth low-speed operation, and “jackrabbit” starts with a minimum speed over 10 or even 20 scale miles per hour (16 - 32 kph) made for poor switching operations. Plus, modelers wanted to model the behavior of real trains, with simulated momentum and realistic braking action.
This led to designs for more sophisticated “throttles” and ever more complex designs as electronics technology improved. Some of the results did a fairly good job of replicating the real behavior of trains, right down to simulating the performance of air-brake systems similar to the one in the diagram at the top of this post. It’s possible some of this took place before the transistor was introduced; vacuum tubes could have been used for similar things. However, nobody appears to have published their experiences with these, so it seem likely that little or nothing was done until the transistor came along.
The development of the low-cost transistor in the late 1950’s made more complex throttles accessible to a hobbyist with a relatively minor amount of electronics skill and for a reasonable price, and the next decade was a time of rapid change, with evolution continuing into the 1970’s. By 1980, interests had shifted towards running multiple trains using command control systems (the precursors of DCC), although the roots of those went back further. And even in 1980 you could still buy rheostat throttles, although they were definitely behind the times by then. None of these technologies fully displaced the others. The transistor has in fact soldiered on into the era of digital controls, and you can still buy transistor throttles today that aren’t too different in principle from those designs of a half-century ago.
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Train Power - DC Motor Basics
13 January 2014 01:00
’m going to kick off the new year with a series of posts on some basic topics related to model railroading. Hopefully that will give me something to think about while my work on the layout is stalled, and reinvigorate my interest. I’m going to start with several about motors and control systems. Much of this recaps material I’ve covered in the past, but hopefully in a more concise and readable form.
Also, since my present modeling is all N-scale, I’m looking at things from that perspective. Much of this is equally applicable to other scales, although Z-scale motors may be somewhat different (“coreless” motor designs are more common there, and I’m not going to get into that).
While many trains today are used on Digital Command Control (DCC) systems, I’m going to focus on non-DCC systems that you’d find in a typical off-the-shelf model or a basic set, similar to the locomotive and DC power pack shown above. The same motors will work with DCC, with some additional electronics (the “DCC decoder”), so this is a good foundation regardless of the type of layout used. Future posts will cover more complex topics, but for now let’s stick to the basics: simple voltage-controlled motors and DC power.
Update: I don’t normally modify Musings after they are posted, but I have made some edits to this one to clarify sections and add some minor details overlooked in the original. These don’t alter the original in a significant way, but may make it clearer to some readers and help provide better background for later posts.
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Also, since my present modeling is all N-scale, I’m looking at things from that perspective. Much of this is equally applicable to other scales, although Z-scale motors may be somewhat different (“coreless” motor designs are more common there, and I’m not going to get into that).
While many trains today are used on Digital Command Control (DCC) systems, I’m going to focus on non-DCC systems that you’d find in a typical off-the-shelf model or a basic set, similar to the locomotive and DC power pack shown above. The same motors will work with DCC, with some additional electronics (the “DCC decoder”), so this is a good foundation regardless of the type of layout used. Future posts will cover more complex topics, but for now let’s stick to the basics: simple voltage-controlled motors and DC power.
Update: I don’t normally modify Musings after they are posted, but I have made some edits to this one to clarify sections and add some minor details overlooked in the original. These don’t alter the original in a significant way, but may make it clearer to some readers and help provide better background for later posts.
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Kato DC Power Pack
22 December 2013 23:11
Several years ago I investigated several DC power packs, including one of my Kato packs (I have three of them). At the time I was reluctant to take one apart because the screws are hidden under the glued-on feet. But a question on the JNS Forum spurred me to investigate the circuitry more closely, and so I took one apart. And in the process, I discovered that some of my old information was wrong.
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Arduino Signals II - Video and Flickering
29 September 2013 00:25
I’ve continued working on the code to drive LED signals with an Arduino. I’d previously discussed my approach, and provided the code I was using at that time. I’ve learned a bit since then, and cleaned up the code significantly. I’ll provide a link to the current example program at the end of this post.
Fundamentally nothing has changed. I’m still planning to use NJI common-anode SMD LED signals (in fact, I’ve ordered them). What I did do was change the code so that a “bank” of two signals would always have both lit (meaning two of the four LEDs would be on when the bank was active) so that I could get through the full set of signals more quickly. One reason for this has to do with video camera shutter speeds. I think it’s worth saying a bit about that issue.
I’ve also made some changes to make the time wasted in turning the pins on and off less, since at these speeds that is becoming a significant percentage of the total LED cycle, and I need that time for the eventual Tram Controller program to be doing other things. These changes consisted of adding a library that provides faster versions of writeDigital and pinMode, as well as keeping track of what state pins are on, and not trying to change them unless the new state differs (this got rid of a number of “change disabled pin X to disabled” changes).
In my test program, when cycling at 8 milliseconds, I’m now spending just a quarter millisecond changing those pins with three banks (6 signals) in use. My One Point Five Meter line will only use four signals, as it doesn’t have the extended double-track section of the full Tram Line, which needs six. And so it will run even more efficiently. Read More...
Fundamentally nothing has changed. I’m still planning to use NJI common-anode SMD LED signals (in fact, I’ve ordered them). What I did do was change the code so that a “bank” of two signals would always have both lit (meaning two of the four LEDs would be on when the bank was active) so that I could get through the full set of signals more quickly. One reason for this has to do with video camera shutter speeds. I think it’s worth saying a bit about that issue.
I’ve also made some changes to make the time wasted in turning the pins on and off less, since at these speeds that is becoming a significant percentage of the total LED cycle, and I need that time for the eventual Tram Controller program to be doing other things. These changes consisted of adding a library that provides faster versions of writeDigital and pinMode, as well as keeping track of what state pins are on, and not trying to change them unless the new state differs (this got rid of a number of “change disabled pin X to disabled” changes).
In my test program, when cycling at 8 milliseconds, I’m now spending just a quarter millisecond changing those pins with three banks (6 signals) in use. My One Point Five Meter line will only use four signals, as it doesn’t have the extended double-track section of the full Tram Line, which needs six. And so it will run even more efficiently. Read More...
Tram Controller Status
31 August 2013 22:47
I’m continuing to work on the Tram Controller project (main page, past musings), to the exclusion of all else layout-related, which doesn’t make for interesting posts here. But I’ve made a number of decisions in the past month, and it’s probably worth summarizing them and where that puts the project overall. Short answer: making good progress, but slower than anticipated (what else is new; all my projects run “slower than anticipated”).
I’ve also been thinking about the diorama-like layout I’m going to initially use this with. The current candidate plans for that are on the new One Point Five Meter Line page.
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I’ve also been thinking about the diorama-like layout I’m going to initially use this with. The current candidate plans for that are on the new One Point Five Meter Line page.
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Signaling with Arduino
19 August 2013 23:43
t seems that I can never resist the impulse to make things more complicated. While working on my Arduino sketch (program) for the Tram Controller, the thought struck me that I could add signals at the stations to tell the fictive operators of the trams when it was safe to leave. These would be “starting signals” in typical Japanese practice, and only require two LEDs, red and green. Of course I’m all out of pins, and the only step up from the Uno, which has 20 pins (14 digital, 6 analog) is the Mega with a whopping 70 pins (54 digital, 16 analog).
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Arduino Controls and a Simple Throttle
14 May 2013 23:03
Having covered the motor control and the sensors, my next step in creating the automated two tram controller was to deal with the very small number of controls I need to have. In my original design, the plan was to have just three pushbuttons:
- Run: when pressed, the trains would start to move.
- Park: when pressed, the trains would return to their starting locations so the system could be turned off.
- Emergency Stop: when pressed, the trains would come to an immediate stop until run was pressed again.
And all three were to be “on when pressed, off when released” pushbutton switches. I was already thinking this needed to be changed, and when I started playing with switches I became even more convinced.
There are two benefits to using toggles versus “on while held” button switches: first, I eliminate a switch, since I need two toggles rather than three pushbuttons. Second, I avoid using those pushbuttons, which have proven to be problematic in my testing. They tend to “bounce” for a long time, and they may remain “on” only for a fairly brief time, making it hard to avoid all bounces and still reliably tell that they were pressed in the first place.
The other control I wanted to add was a way to customize the top speed of a train (or trains, really), so the different models could be made to run at similar (and prototypical) speeds. I don’t want one train rocketing down the tracks while the other creeps along, even if they have very different motors and gear-trains. So I’m going to add a pair of potentiometers, used as “tram #1 max speed” and “tram #2 max speed” controls. And note that these are for the trains, not the motor shield A/B outputs. At various times each tram will be controlled by one or the other.
My first step was to create a simple throttle that used one pot, three switches, and one motor control to run a train on a simple test track. This gives me a proof-of-concept example that ensures I really understand what I think I understand (always a concern with me and electronics).
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- Run: when pressed, the trains would start to move.
- Park: when pressed, the trains would return to their starting locations so the system could be turned off.
- Emergency Stop: when pressed, the trains would come to an immediate stop until run was pressed again.
And all three were to be “on when pressed, off when released” pushbutton switches. I was already thinking this needed to be changed, and when I started playing with switches I became even more convinced.
There are two benefits to using toggles versus “on while held” button switches: first, I eliminate a switch, since I need two toggles rather than three pushbuttons. Second, I avoid using those pushbuttons, which have proven to be problematic in my testing. They tend to “bounce” for a long time, and they may remain “on” only for a fairly brief time, making it hard to avoid all bounces and still reliably tell that they were pressed in the first place.
The other control I wanted to add was a way to customize the top speed of a train (or trains, really), so the different models could be made to run at similar (and prototypical) speeds. I don’t want one train rocketing down the tracks while the other creeps along, even if they have very different motors and gear-trains. So I’m going to add a pair of potentiometers, used as “tram #1 max speed” and “tram #2 max speed” controls. And note that these are for the trains, not the motor shield A/B outputs. At various times each tram will be controlled by one or the other.
My first step was to create a simple throttle that used one pot, three switches, and one motor control to run a train on a simple test track. This gives me a proof-of-concept example that ensures I really understand what I think I understand (always a concern with me and electronics).
Read More...
Detecting Trains with IR Sensors, Part II
04 May 2013 00:11
This is going to be a short post: it’s working! I have my IR LED phototransistor sensor program detecting things (not trains just yet), and I’ve posted the example code, see the bottom of the Tram Controller page for a links to that, and the earlier motor control code. Both example programs are public domain, feel free to use them however you see fit. I’ve benefited from a lot of public domain programs, and I think it’s only fair to give something back. When the tram controller program is a bit more polished, I plan to publish it in the same way, although it may be months before I get to that point.
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Detecting Trains with IR Sensors, Part I
30 April 2013 01:02
In my continuing work on the Arduino-based Tram Controller, I’m now playing around with the part I really wanted to work with, the Infra-red optical sensors themselves. This turned out to be rather more complex than I’d anticipated, but I’m most of the way there, even if I don’t quite have the system working yet. This is a post about what I’ve done so far, and what I’ve learned, with a bit about what remains to be done.
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Arduino CPUs and Motor Shields
21 April 2013 22:08
I’m still playing with Arduinos this week, but the little beasties are multiplying. That’s partly because I want to be able to test with the various CPU architectures, but also because each has unique strengths and weaknesses, and I’m still evaluating which of them is going to be the right choice for my tram controller. At the same time, it turns out that there are a number of options for motor shields, as I mentioned last time, and they too have strengths and weaknesses.
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Revisiting Arduino
14 April 2013 23:45
Two years ago I wrote about my plans to use an Arduino to control a pair of trams on a double-track line sharing single-track stations at each end, replicating the design of the Tōkyū Setagaya line. That’s briefly written up in that earlier post, and I also have a full page about the project that goes into more detail, with a sub-page about the current testing work.
Back then I bought an Arduino Mega 2560 and a bunch of other parts including a “shield” used to drive DC motors, loaded the basic test program that blinks a LED into it just to convince myself I could do it and the hardware worked, and then put it on a shelf for “later”. And forgot all about it while I worked on other things, only infrequently looking at the empty tram tracks and thinking “I really should figure out how to make that work.” It’s not like I dislike the work: I enjoy both programming and soldering simple circuits together. I just never could work myself up to starting what I expected to be a fairly major project. It was always: “I’ll work on that after I finish project ‘X’”, but there was always another “X” to occupy me.
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Back then I bought an Arduino Mega 2560 and a bunch of other parts including a “shield” used to drive DC motors, loaded the basic test program that blinks a LED into it just to convince myself I could do it and the hardware worked, and then put it on a shelf for “later”. And forgot all about it while I worked on other things, only infrequently looking at the empty tram tracks and thinking “I really should figure out how to make that work.” It’s not like I dislike the work: I enjoy both programming and soldering simple circuits together. I just never could work myself up to starting what I expected to be a fairly major project. It was always: “I’ll work on that after I finish project ‘X’”, but there was always another “X” to occupy me.
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Other Lightboards
31 December 2012 23:29
Up until now I’ve been concentrating on my Kato models as far as DCC conversion goes, and at the same time I’ve only really paid attention to the interior lighting of those cars. Now that I’m working up to large-scale DCC conversion of my non-Kato stock, which is mostly MicroAce and Greenmax at this point, I need to think about lighting the interior of those cars.
And it turns out, they’re pretty much identical. Both MicroAce and Tomix make their own interior lighting kits, and they’re very similar. A third-party company, F&MOKEI also makes lightboards, and claims they work with both manufacturers’ cars. And Greenmax notes compatibility of its cars with Tomix lights (Tomix is far larger a company than MicroAce, so it makes sense they only mention one).
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And it turns out, they’re pretty much identical. Both MicroAce and Tomix make their own interior lighting kits, and they’re very similar. A third-party company, F&MOKEI also makes lightboards, and claims they work with both manufacturers’ cars. And Greenmax notes compatibility of its cars with Tomix lights (Tomix is far larger a company than MicroAce, so it makes sense they only mention one).
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Wire
16 December 2012 02:55
I went off on a tangent this past week. It all started when I asked myself: what gauge wire should I use on my decoders? And the root of that question was thinking that the wire I’d used on my first install, two weeks ago, was too thick. The answer turned out to be less obvious than I thought it would be, and consumed (and is still consuming; I’m not done) a lot of time.
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Some More Lighting
23 August 2012 23:26
Work on the layout continues slowly, but I now have the second lighting unit assembled. The wiring is still rather temporary (the orange extension cord is not a permanent feature). It is working very well, however. My software things the color of the light is around 4150K, or perhaps a bit lower. The intensity is quite good, allowing me to take photos with a fairly large depth of field. The one above was taken at f/8, at 1/50-second exposure. I could easily halve that without using a tripod, or go lower with one. There’s a large amount of glare off the top of the backdrop, apparent in the photo above. You don’t really noticed it standing in front of the layout, because the top of the backdrop is hidden by the edge of the valence.
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Let There Be (More) Light
27 July 2012 22:05
I finally decided to experiment with fluorescent tubes, after living with the track-lighting with CFL (compact fluorescent light) bulbs I’ve used to light the layout for the past two and a half years. I’m sorry I waited this long. The new fixtures, the first of which is shown above, weren’t cheap, about US$90 each by the time you add up all the parts. And they’re fiddly to hang properly given my less than perfect basement ceiling. But I’m getting twice (or more) the light from one 26W bulb that I was from four 14W ones, and it’s much more even lighting. I’m still debating using two tubes on the fixture, although that will raise the cost each substantially.
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June 2012 Status - What, its not June
14 July 2012 18:01
Yeah, this is a bit late. I’ve been distracted. I’m throwing this up so I can summarize what did get done, before moving on.
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More Wires
10 April 2012 01:35
After saying I was going to finish up the DCC electronics several times, I’ve finally made a start. There are two parts to this. The first is finishing up the remaining DCC power protection and occupancy detector panels. I did the first three tables last year, starting around January. The third was the first I’d done as a removable panel, which I wired up back in November. At the same time I’d begun the work of setting up a third accessory power bus, adding a switch and meter to the main panel. However at that point I’d stalled, with my attention off the layout over the holidays, and when I returned it was to work on buildings.
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Bus Wiring and November 2011 Status
03 December 2011 22:48
DCC is often said to simplify a model railroad because it requires “only two wires”. While that’s true to an extent, most real model railroads will require quite a bit more. Or maybe I just like to over-complicate things.
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Wiring Without Solder
11 July 2011 22:21
Well, I’m not moving the site just yet. Conversion of pages is going more slowly than expected, and there are more pages that I consider necessary than I first thought there would be. So I’ll probably have a few more posts over the next couple of weeks before switching over to the new software and hosting provider. However, for the curious I’ve included some jpegs of the new main page and one of the subordinate pages showing the new layout and navigation links in the Diagrams album (these are reduced somewhat by iWeb; the type used for text on the page is about the same or slightly larger than the type used today).
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DC Signals I: Kato
27 June 2011 22:22
This is the first of what will probably be two postings about simple trackside signals for DC layouts. This one will discuss the basics common to the Kato and Tomix signal systems, and then provide details about Kato. Since I’m partly looking at the Kato to see if it’s a good candidate for modification for my DCC layout, I’ll have a few comments on that as well. A future posting will cover Tomix’s richer offering, which I’m looking at for use on my DC Urban Tram Layout (which will probably use the Tomix signals), although the four-color signal heads might be something I could use for my DCC layout (nobody in the U.S. makes a four-lamp signal of this kind).
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How I learned to stop worrying and love the BDL168
08 March 2011 00:39
Well, perhaps that’s a bit strong, but I’m coming to terms with its design flaws and the poor state of the documentation surrounding it and the PM42. I now have the first set of PM42 circuit breakers and BDL168 occupancy detectors (with two sets of RX4 “transponding receivers”) installed, and have done a bit more reading over the weekend. I’ve discovered a few things and come to a few conclusions as a result of that work, and that’s making me feel that I have a handle on this now. But I had to work through a number of issues to get to this point.
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February 2011 Status - Occupancy Detection Revisited
03 March 2011 23:43
Work has progressed slowly this month, partly from distractions, and partly because I’ve been reluctant to finish up the block occupancy detector wiring. I finally realized that the reason for this was that I wasn’t happy with my hybrid approach to occupancy detection and transponding.
To recap, my Subway and Commuter loop tracks were to be divided into blocks, with Digitrax BDL168 occupancy detectors and PM42 circuit breakers (circuit breakers are typically one per track per table, whereas there may be two, three or even four detectable track sections on a single track on one table, and more in a couple of cases). The PM42 provides for four circuit breakers, which is a nice fit for the four tracks, and the BDL168 is divided into four independent quadrants (so each can be wired to a separate circuit breaker), each with four block detectors. I’d originally planned one PM42/BDL168 per scene, meaning that wires would have to cross a table boundary in the Urban and Riverside Station scenes.
And that was a problem, for several reasons. First, running wires between tables violates my “keep all wires except bus wires local” design goal (it makes the layout harder to disassemble), second while the BDL168 can support 16 occupancy detectors, in some places I needed more than four on one track, which broke the association of the PM42 circuit breaker element to a single track, meaning a short would shut down a second line. And finally, I wanted to do Transponding, and the BDL168 only supports 8 transponding sensors (using a pair of RX4 sets), meaning some blocks would be able to report which train was in them, and some would only be able to report that some train was present, but not which. None of these were fatal flaws, but they were eating at me. And I finally realized that I only needed two more sets (seven instead of five) to fix these problems.
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To recap, my Subway and Commuter loop tracks were to be divided into blocks, with Digitrax BDL168 occupancy detectors and PM42 circuit breakers (circuit breakers are typically one per track per table, whereas there may be two, three or even four detectable track sections on a single track on one table, and more in a couple of cases). The PM42 provides for four circuit breakers, which is a nice fit for the four tracks, and the BDL168 is divided into four independent quadrants (so each can be wired to a separate circuit breaker), each with four block detectors. I’d originally planned one PM42/BDL168 per scene, meaning that wires would have to cross a table boundary in the Urban and Riverside Station scenes.
And that was a problem, for several reasons. First, running wires between tables violates my “keep all wires except bus wires local” design goal (it makes the layout harder to disassemble), second while the BDL168 can support 16 occupancy detectors, in some places I needed more than four on one track, which broke the association of the PM42 circuit breaker element to a single track, meaning a short would shut down a second line. And finally, I wanted to do Transponding, and the BDL168 only supports 8 transponding sensors (using a pair of RX4 sets), meaning some blocks would be able to report which train was in them, and some would only be able to report that some train was present, but not which. None of these were fatal flaws, but they were eating at me. And I finally realized that I only needed two more sets (seven instead of five) to fix these problems.
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Almost There - January 2011 Status
04 February 2011 22:38
January went primarily to the backdrops and the risers/inclines of the Riverside Station scene commuter loop, and now the Riverside Station scene begins to come together. The tables themselves are not yet connected to each other or anything else, as I’m taking the opportunity to work on the wiring with them stood on edge, which is much easier than working on it from below.
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Building A DCC Booster
25 January 2011 01:45
It’s been longer than usual between updates. That’s partly because other things kept me away from working on the layout or this website (the layout is still apart awaiting final assembly of the backdrops), but mostly it’s because I’ve been spending evenings the last couple of weeks building and testing a DCC booster kit. I didn’t actually need another booster, but Don offered me one and it seemed like a good way to gain some soldering experience (which it was, although I had a bit of a scare when it didn’t work).
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Freight Trains, Electronics and October 2010 Status
01 November 2010 23:27
Not much got done on the layout itself in October, mostly I’ve been running trains (as documented in an earlier post with a video) and doing a bit of electrical work (mostly the previously noted update to the power panel). I’ve spent a good bit of time on a couple of other things though.
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Adding a DCC Meter, And Related Topics
22 October 2010 00:54
Although I wrote about the power panel previously, there were a couple of things left undone. I was missing one of the ammeters for the lighting power (the store I get them from had run out), and I’d misplaced one of my LNRP LocoNet Repeater panels, so I’d substituted a UP5 panel I took off the old HO layout. Also, I’d realized that my portable RRampMeter DCC volt/amp meter was useful, but wiring it into the system when I wanted to check something was a real nuisance. Over the summer I bought or found the missing bits, and finally decided to order a new RRampMeter (the version without the nice case) to mount as a permanent part of the circuitry (I’m keeping my other meter--the one with the case--for workbench and other testing uses). So it’s a good time to summarize what the panel does, and talk about the new meter a bit.
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Track Voltage, Motor Voltage, and DCC
22 August 2010 19:38
As I’m finishing up the wiring for the two upper-level loops (one of which will be DCC-only, the other will be the switchable DC/DCC line), I’m also getting my DCC electronics set up and ready for use. There are several aspects to this, and I’ll cover others in future musings. But today I’m going to write about track and motor voltage. I could have just used the command station as it came, and it probably would have worked fine. But I like understanding exactly what’s going on under the hood, and so I ran a number of tests and spent some time researching what the track voltage should be, and why, and what that meant for the motor on a train. And if I ever add a booster, it will be important for it and the command station to be set to output the same voltage (this avoids problems when a train bridges between two power districts), so I may as well pick a voltage now.
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July 2010 Status - Behind the Scenes
02 August 2010 01:05
Much of July went to more electrical work, partly planning, but mostly just crimping spade lugs to wires. Around 200 of them this month. There are now a total of six bus wire pairs beneath the tables: two for DCC (command station and future booster), two for the two tracks of the outer (Rapid/Shinkansen) loop, which will be switchable from DC to DCC, and one each for DCC accessory power and the Occupancy Detector & Signaling systems. I also wired up the control panel for the power.
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Scotty I Need More Power!
25 July 2010 00:12
DCC doesn’t need to be complicated. At the simplest, it’s a pair of bus wires from the command station running under the track, with feeders connecting the track to it at intervals. I can, however, make anything complicated. Probably more complicated than it needs to be. It’s a talent.
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More Electrical Work
20 June 2010 23:16
Rather than turning my attention immediately to the Riverside Station scene, I decided to get the electrical systems ready for the eventual use of the two “ground level” loops, which will require DCC. And that meant I needed to finalize my plans. And although most of them had been worked out last year, and revised (in my head if nowhere else) over the winter, there was still a bit of planning needed before I was ready to start cutting wire. This had to encompass the DCC systems (both power and the LocoNet control bus) as well as the various power strips to supply them, and some additional power supplies for eventual LED lighting. I’d started thinking more intensely about this while I was working on the wiring recently, but needed to bring that to conclusion and write down the results.
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Subway Track Cleanup, Etc.
07 June 2010 00:32
This weekend went largely to the beginning of the final (I hope) laying of the subway track, which has been in place, in whole or in part, through more than six months of construction. As a result, it has gotten a bit dirty. All track was pulled up, cleaned with isopropyl alcohol on a cotton pad, and relaid. At the same time, insulated unijoiners (black, in the photo above) were inserted to divide the track into electrical blocks (for power feeds and future occupancy detectors) and power feeds were wired up to terminal strips under the table. I didn’t get it all done, perhaps a bit more than half, but I should be able to finish it during the week and run trains by next weekend.
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May 2010 Status - Carving Foam
31 May 2010 23:31
Time marches on, but it seems to be crawling on the banks of the Sumida. The hillside covering the subway has made little apparent progress over the last month, going from squarish blocks of pink foam to carved, but still pink, sections, which only just received a first coat of primer (and have yet to be glued in place).
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March 2010 Status - An Urban Station, almost
04 April 2010 01:01
Another month, and it seems like there isn’t much to show for it. That’s somewhat deceptive as many things have been accomplished, but nothing has been finished, and that makes it seem like less was done. I’ve covered most of this already, so I’ll quickly summarize the work. Read More...
January 2010 Status - Planning the Upper Level
30 January 2010 22:34
This month was spent thinking about the track that will go on the upper (ground) level, above the subway. I never actually did finish wiring up the subway loop (although I can run trains on it using DC, they get a bit slow on the opposite side of the loop from the powerpack; rail is a poor conductor of electricity). Read More...
What Color Is My Light?
05 January 2010 01:02
Lighting the layout isn’t something I’d expected to spend a lot of time on. I had existing lights that worked on my old layout, and I planned to continue using them. Initial experiences, and some problems with color accuracy in photographs, led me to do more investigation, and to ultimately change my plans. Read More...
December 2009 Status - Subway Track in Place
31 December 2009 01:55
The subway level track is nearly complete, with the underlying foam and cork glued down, and the Unitrack in place. Read More...
September 2009 Status
29 September 2009 02:58
The tables (phase 1, excluding the end section with the helix) are all assembled and mounted to the legs, with scenery backdrops and paint. That’s taken more than a month (after a couple of months of planning, mostly deciding on a track plan). I’m still in the design phase for the electrical systems. After some experiments with foam height and bridges, the design of the subway (and its implications for how many foam layers I will use) is done (I hope). Read More...
