Back in the 70's and early 80's I built power supplies - Radio Shack was a ready source for the componets liek transformers, toggle switches, neon lights, fuse holders, bridge rectifiers..and metal project cases. Which I never grounded. I think I made 3 in total, a 6.3V one, a 12V one, and one using the 18V CT transformer to get a +/- 9V for op amp circuits.
Way back in the day, when copper oxide rectifiers were new (and horrible), many modelrs ran with car batteries. Most any article I can remember reading in goign through the archive (I have the DVD version, started at the very first issue and read them all in order) either had a fuse or, if missed by the author, the next month's issue had a note that you had better use a fuse because car batteries can dump a lot of current into a short. ANd in those days - it took TWO car batteries, because they were all 6V. Yes, there were some crazy things - like in the first issue, the guy with the outdoor trolley layout using 110VAC in the overhead. Burn your house down? Not very likely. Give someone a shock? Well, if they were stupid and touched the wire. Obviously the guy had no little children runnign around, and no pets (the article does mention that there is no indication of the effect on the locl squirrel population - sort of indicating "Ed." (probably Al Kalmbach himself) thought this was a rathe rsilly idea and no one should duplicate it. But that was also a time when you didn;t have to say "don't try this at home" on everything even remotely dangerous because people weren't that dumb. I don't think anyone tried to drive their Model T between two trolley cars because the Keystone Kops could do it. As for bare connections - at the time a lot of homes would still have knob and tube wiring. e think that was insanely dangerous by todays standards - but was it? The two conductors were widely spaced, certainly not in a position where some overheating could melt insulation and cause a short. Or where a nail driven in to a wall could pierce the wire and short things out. When passing through wood beams, the wire was run inside the ceramic tubes - pretty well heat insulated from the wood so as to keep a hot wire from igniting the structure. All in all not really horrible, unless you flail away and grab both live wires.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
dknelsonThe earliest edition of Westcott's wiring book spent more time and space on making your own power supplies from scratch, so there was more than a little 110 volt wiring in there that by today's standards would, yeah, not be "UL approved," including some of the troubleshooting suggestions.
.
My copy of Wescott's book is from the early sixties. I think it is the third printing.
It still contains information on different voltages and frequencies in different locations in the USA, even though I think by the 1960s we were standardized.
The uninsulated AC connections and various speed controls are scary. Your house would be a concern, dogs and children were also in danger!
Reading Model Railroader from 1946-1955 also includes all kinds of questionable wiring ideas.
-Kevin
Living the dream.
rrinkerCurious about the "how to burn your hose down" dig at Westcott's book, I've never seen anything particualrly dangerous there - considering he is dealing with the low voltage trainc ontrol side of things. The book covers several differnet methods of cab control for DC operation, each has its own pros and cons in regards to simplicity and flexibility of control, but none of them seem to be designed to make it easy to set you layout on fire.
The earliest edition of Westcott's wiring book spent more time and space on making your own power supplies from scratch, so there was more than a little 110 volt wiring in there that by today's standards would, yeah, not be "UL approved," including some of the troubleshooting suggestions.
While a little bit of that was left in the final edition by that time it had been re-written to reflect that almost all readers, even those with big layouts, would be buying commercial power supplies.
Dave Nelson
Greg,
I completely agree, there are situations where software is the easier solution.
But just like the DC or DCC question, one size does not fit every situation.
As for the track diagram you posted, I would be interested to see a scale drawing of the track. It sems unlikely that it would desireable to have every possible complete route as a choice, but rather it should be broken down in to sections, which would simplify the logic, hardwired or software.
But I could be wrong about that.
On a typical interlocking on my layout, as stated, it only takes one or two relays per turnout to get the needed logic. You remember of discussion about the wye.
As a relay logic designer, I never use latching relays, they cost a lot more. Too easy to just seal a relay on with a contact. But I understand why you would need/want them with solid state logic.
AND, most important, many of the products being used today for software type solutions did not exist, or were not affordable, or readily available 15-20 years ago when I began developing my control system.
Which speaks to a simple fact, once people are invested in something that works, why change it just to change? If we started from scratch tomorrow, we could build something better than DCC, but it won't happen, because DCC works just fine.
And, being a building design professional I would likely agree with your heating choice as well.
Sheldon
ATLANTIC CENTRALSo why do you need a computer or micro processor to do what one 4PDT relay per block detector and turnout can do? Less wire? Not really.
ATLANTIC CENTRALSimply select the desired route, and assign the primary blocks on either side to your throttle and the power is automaticly routed thru. The same relays do this as well. They too need to be able to handle the 5 amps. So where is all this savings in wire?
it's a bit more than just block detection and turnouts. since you're DC, you need the 5A relays to control power to the track, and since you're familiar with relay logic, you're comfortable using the same relays for block detection and turnouts.
the context of the problem can make one solution economical for one person but not another. I looked at high efficiency heating and concluded that it wasn't economical for me when I replaced my system. What I realized is that in a new home, the high efficiency furnace saves the cost of a chimney.
in your case, relays do power routing. But I don't think this is an issue if you're using DCC (there's no need for a chimney).
where wiring can be saved is using nodes as Bruce Chubb described. Nodes can provide provide I/O to nearby devices such as block detectors, turnouts and signals. Node can also connect to panel switches and lamps. All nodes can be connected on a single 4 wire (RS-422) bus. And a computer can connect to the node bus through it's serial interface.
One node can monitor block detection on a long block while two separate nodes control signals at each end of the block. Even on medium layouts, the reduction in wire can be significant.
instead of having long lengths of wire stretched across the layout, connections are to the nearest node, and if one isn't available, you can add on.
but the other aspect of processors is there ability to solve some problems that may become too intractable using hardwired connections.
I helped complete a route selection panel. An arduino and several MCP23017 I/O expanders control turnouts to select the route between pairs of buttons on the panel. There's nothing more to the wiring than connections to buttons, lamps and latching relays controlling each Tortoise. Route selection is logic in the code.
after installation, the problem was not all the routes were supported and there were mistakes. After looking over the code and making corrections, the processor was simply reprogrammed. Someone made a comment that it would be nice if ... and it was quickly tried out.
ATLANTIC CENTRALHard wired logic works fine......
I think attempting the above routing panel with hardwired logic would be challenging and most would not attempt it. The software solution made the hardware simple and corrections easy to make. The software approach makes the problem less challenging because it's easy to fix mistakes. (some would say 600 lines of code is too much).
greg - Philadelphia & Reading / Reading
gregc rrinker Good engineering is using the most appropriate component for the task at hand, not just the latest thing. processors are good for logic and in some cases still rely on (latching) relays for controlling higher current devices. it's good to have more than one tool in the toolbox. ATLANTIC CENTRAL So why do you need a computer or micro processor to do what one 4PDT relay per block detector and turnout can do? Less wire? Not really. because a single processor can often replace more than one relay and often serve multiple purposes (e.g. signal control, communication node, servo controller, ...) at the same time, and can significantly reduce wiring and maintenance
rrinker Good engineering is using the most appropriate component for the task at hand, not just the latest thing.
processors are good for logic and in some cases still rely on (latching) relays for controlling higher current devices. it's good to have more than one tool in the toolbox.
ATLANTIC CENTRAL So why do you need a computer or micro processor to do what one 4PDT relay per block detector and turnout can do? Less wire? Not really.
because a single processor can often replace more than one relay and often serve multiple purposes (e.g. signal control, communication node, servo controller, ...) at the same time, and can significantly reduce wiring and maintenance
In the early 1980's I was wiring and programing some of the first Programable Logic Controllers being used to replace relays in industrial applications.
I was responsable for one of the very first of such applications of PLC's to run a waste water pumping station here in Baltimore.
I get it.
But that's just it, in my application I don't need all that. But I do need high current handling and discrete switching.
I use Dallee inductive dectectors which have a DPDT relay output.
It then only takes one 4PDT relay per turnout (averaged out over the whole system) to provide all the signal logic and power routing logic for the whole system.
My dollar cost average to aquire the sealed ice cube relays is less than $2 each.
All the other equipment I would still need, trackside signals, LED lighted push buttons and LED panel indicators on the tower panels and the CTC panel being the main other components.
Nothing would reduce the input/output wire count from my signals and panels to the logic.
I will not use computer or touch screen input interfaces - I don't like them - I want the tactile feel of real buttons.
Being a DC operator, I need to connect the primary blocks to the wireless throttle base stations.
This too is done with pushbuttons, from multiple locations. Cabs can be assigned to a primary block at the CTC panel or at the local tower panels.
Pushing a button to assign a given throttle, disconnects any previously assigned throttle. This needs to switch both wires of the 5 amp power supply. Each throttle has its own seperate power supply.
This is done with a relay bank of 8 relays on a printed circuit board with stop/start station logic, which allows unlimited input locations. I typically have three locations for each primary block, the CTC panel, and the tower panel at each end of the block.
And again, no solid state device would provide the necessary discrete switching needed to keep the power supplies isolated, nor would a solid state device eliminate wires, the circuit board has already eliminated as many as possible.
Interlockings (a turnout or related group of turnouts) are special X section blocks. They do not have to be manually assigned to a throttle.
Simply select the desired route, and assign the primary blocks on either side to your throttle and the power is automaticly routed thru. The same relays do this as well. They too need to be able to handle the 5 amps.
So where is all this savings in wire?
OK, yes, I have relay panels with lots of logic wiring. Easily wired on the work bench.
But the number of wires from those panels out to inputs and outputs would be no less with solid state logic, and then I would have to convert a lot of the solid state logic to discrete power level switching (relays) anyway - sound like more layers and more wire.....
Maintenance? Never had one of these 24 volt ice cubes fail, not even the $2 Chinese models, surely not any of the domestic ones bought surplus for less than $1 each.
The layout control system I built and installed on a friends layout has worked trouble free for 10 years now.
An important factor here is that I do not want computer screens or smart phone interfaces........
You could not build a solid state solution to my needs for less money than what I have spent using mostly relays.
I considered all sorts of solid state solutions 12 years ago when I developed this control system. None where easier to impliment or less expensive then what I came up with.
I even considered putting the whole thing on a PLC but would have still needed lots of relays for discrete high curent switching.
Hard wired logic works fine......
rrinkerGood engineering is using the most appropriate component for the task at hand, not just the latest thing.
To be fair, you are comparing people from different generations. Most of Westcott's ideas, for example, were published before or while Bruce Chubb was just experimenting operations with Lionel trains, long before CMRI or the parts that made it possible were available.
And Westcott went way beyond cab control schemes - he came up with the Twin-T detector, and various TAT throttles. Not bad for a guy educated in the days of relays and vacuum tubes. ANd of course he did a lot more than just electrical stuff.
Too many these days seem to think the only solution is the one using the latest and greatest components. Good engineering is using the most appropriate component for the task at hand, not just the latest thing. Sometimes a relay just does a better job - solid state relays are not just drop in replacements for all uses.
A few more thoughts:
Paul Mallery, Ed Ravenscroft, and Bruce Chubb all were way ahead of anything Linn Westcott was doing.
But I agree, Westcott covered the basics just fine.
Ravenscroft and Chubb in particular used relays very effectively and their signal and control systems and are well documented in MR.
Their signal systems, turnout control systems and CTC systems will in fact work just as well today with DCC as they did back then with DC.
It seems to me that too often modelers fail to define their goals before they go looking for equipment and methods to meet those goals.........
Do you really need/want permissive block signals? Do you have dozens of miles of desolate mainline between interlocking points on your layout where you intend to stack up trains moving across the country side?
Or do you really just need the control point interlocking signals? And maybe a few approach signals?
So why do you need a computer or micro processor to do what one 4PDT relay per block detector and turnout can do? Less wire? Not really.
There are times where solid state is the best answer - I use solid state inductive detectors, solid state regulated power supplies and solid state wireless radio throttles.
But solid state solutions for my turnout controls, signaling, cab selection and power routing would have no cost, performance or installation advantages. Here relays shine, being both a logic device and a power switching device in one.
Sound engineering principle suggests we should define the goals before we consider solutions. Today it seems model railroaders often see someone elses solution, and try to fit their needs into it?
Still marching to my own drum, quietly in my own head....
My formal electronics eduation began well after the introduction of the microprocessor, let alone logic ICs. I STILL think relays are perfectly valid devices for power switching, even with DCC. The relay switches plenty fast enough to prevent sound decoders from stopping, even without keep alives. I've been holding my tongue on recent posts on the NCE group where Bruce Petrarca has been badmouthing relays as old and slow. in a discussion on autreversers. It's not the relay that matters, it's how fast the rest of the circuit detects and triggers the relay that matters. I fully plan, for simple reverse sections, on using switch machine contacts to drive a relay to swap the track polarity instead of buying a fancy autoreverser. My one and only job where i actually did any electrical engineering involved large machine tools, racks fo computer boards which at least in the case of the spindle drives almost 100% used relays to switch the power. The axis servos - not steppers, not in a precision machine tool - were driven with power transistors or, on the newest machines, used AC motors. The one thing that was directly driven from solid state components were our EDM machines, basically shorting and sparking through bansk of 2N3055 power transistors. I think each module was 5 amps in most of the machines we had, and you just plugged more modules in to each rack chassis to gain power. I want to say each rack cage held 10 modules, so each rack unit was 50 amps. These were made by some company in Englad, and each of the actual power modules with the transistors seriously looks like it was soldered by some 8 year old kid in their basement. I rebuilt countless numbers of these, we kept a large inventory of known good ones to reduce shop downtime, just swap out a failed one to get the machine back up and set th ebad one aside for later troubleshooting and repair. When inventory dwindled we'd sit down at the bench and go through the bad ones and fix them. The really didn;t last long with this abuse, a heavily used machine could have half its modules swapped out in a week. We did design our own and had a test machine using our own circuit but other than a few test parts it never got run in production, management would rather just buy a case of 2N3055's at a time and have use repair the other ones.
Curious about the "how to burn your hose down" dig at Westcott's book, I've never seen anything particualrly dangerous there - considering he is dealing with the low voltage trainc ontrol side of things. The book covers several differnet methods of cab control for DC operation, each has its own pros and cons in regards to simplicity and flexibility of control, but none of them seem to be designed to make it easy to set you layout on fire.
$6.00 from Amazon, $3.99 for shipping. Hard cover.
No, not that bored yet. But I grew up with stuff like that in the 1950's.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
Unfortunately I can't see the image of the book, but I'm guessing it's "Model Railroad Electronics" by James Kyle, based on the later posts. Interesting that the cover blurb mentions "command controls"?
SeeYou190 I was talking about using relays as logic gates. AND, OR, NAND, and NOR. . Of course I know there are many uses for relays. . . -Kevin .
I was talking about using relays as logic gates. AND, OR, NAND, and NOR.
Of course I know there are many uses for relays.
Yes, I understand. And yes, as I explained I use them as logic gates.
They control my signals, they automaticly route track power, they set up interlocking routes with one button.
Inputs = detection, turnout position, CTC permission, throttle assignment to track sections, all in the form of relay contacts.
Outputs = logic path for each signal lamp from power supply, logic path from throttle base units to track sections, logic path directing track power based on turnout position.
Same circuits that the prototype has used since the beginning of signaling. Just now starting to be replaced on a large scale with solid state.
Here is how I use them as logic gates for route control of turnouts, like this three button control for a wye:
By using relays, the additional contacts can route track power, power frogs and logic the signals with no additional equipment or layers.
And using the standard machine control start/stop station circuit, redundant controls can be placed in parallel as many times as needed, as shown on this drawing as "local" and "CTC".
Here is how those same relays both throw the turnouts and route the power:
Yes, ocassionally I need more contacts and need a repeater relay. But generally the 4PDT relays provide all the logic needed.
The relays I use have 5 amp contacts, my average price to acquire is $1.50 per relay.
The whole mainline can be run from the CTC panel or in walk around mode from local tower panels.
SeeYou190 OK, I will play along. . I thought the title was 100% accurate, because I am fascinated by the subject matter, and the trip back in time. However, the book is extremely academic and very hard to keep reading, so it is boring also. . I believe in the 1970s we could by ICs at Radio Shack that had for "AND", "OR", NAND" or "NOR" gates in them for a couple bucks. Why go through the mess with relays for a model railroad? . Keep the suggestions coming. . -Kevin .
OK, I will play along.
I thought the title was 100% accurate, because I am fascinated by the subject matter, and the trip back in time. However, the book is extremely academic and very hard to keep reading, so it is boring also.
I believe in the 1970s we could by ICs at Radio Shack that had for "AND", "OR", NAND" or "NOR" gates in them for a couple bucks. Why go through the mess with relays for a model railroad?
Keep the suggestions coming.
Why use relays?
They offer discrete switching at the power level.
They allow for intergation of both power and control information with less "layers".
They have become cheap and reliable, espeically in the last 20-30 years.
I use 24 volt ice cubes with 4PDT contacts to run my Advanced Cab Control which fully intergates turnout control, detection, CTC, and throttle selection into one system.
Unlike typical DC cab control, I use the relays to automaticly power X sections (think of them as sub blocks between major blocks, like a crossover) based on turnout positions, eliminating over half the "block controls". And the block controls are done with a relay matrix that allows the use of pushbuttons in multiple locations for both cab selection and turnout position locally and on the CTC panel.
Pushing one button selects complete routes like wyes, complex crossovers, and returns other turnouts to their default positions.
When I was developing my control system, no solid state solution offered lower cost or easier installation - still the same today.
I do use solid state inductive detectors made by Dallee - and their output is - relay contacts.
Those relay contacts in series with relays that repeat the turnout status (because those relays control the turnout) is the entire logic for the signals - no drivers or other layers needed.
Believe me, I looked at everything out there, this was the easiest and least expensive way to meet my goal of both local and CTC panel control and signaling.
A similar system I build for a friend is still working fine after 15 years.
At that time (the 1970s ) the IC could not handle the current for the switch machines in use at that time.
Maybe for some lights, but a toggle switch worked just as well.
I typed "James Kyle" into the magazine index on this website (a rare instance where I could actually get it to work!) and the man seems to have left no footprint in model railroad publishing other than this book. No other articles that I could find - and that index covers dozens of magazines, many now long gone of course.
Books about wiring and electronics tend to be difficult for me to read or find interesting - and oddly, almost all of them describe themselves as being "easy" and "practical." For lies of that magnitude you'd normally need to go to a dating website .....
or so I've been told
That's ok, I'll watch. I never would have a book like this anyway, I don't like the pictures.
I wonder what the last check-out date on the library card would be?
Mike.
My You Tube
Let's start a petition to get Kevin to change the title.
Or, start a contest to pick the most appropriate title.
I'll go first. How about Interesting but Mind Boggling Book?
Alton Junction
riogrande5761That's the first thing I thought of. Aren't they sort of mutually exclusive.
That's almost exactly what I was thinking
Regards, Ed
richhotrain But, how can a book be both fascinating and boring? LOL Rich
But, how can a book be both fascinating and boring? LOL
That's the first thing I thought of. Aren't they sort of mutually exclusive.
Seems we can always count on frequent new and bizarre topic titles here at MR forums.
Rio Grande. The Action Road - Focus 1977-1983
Reminds me of my favorite unreadable book “IBM 370 Principles of Operation“
Joe Staten Island West
rrinkerThe classics were always Linn Westcott's and the two volumes of the Paul Mallory ones.
I have a second printing copy of Linn Wescott's book. I have often thought that book should have been titled "How to Burn Your House Down".
richhotrainBut, how can a book be both fascinating and boring? LOL
I read lots of technical manuals that are difficult to get through, but the subject matter is completely engrossing.
I would not be surprised if the text is actually much older than 1977. I was experimenting with Tandy-Kits and bread boards in 1977, and I remember a lot of components being available that are not even mentioned so far in the book.
I would bet this book was already outdated in 1977.
I think I have a copy of that packed up somewhere.....
Having been a young adult working in electrical engineering in 1977, and being a model railroader for nearly 10 years at that point, "electronics" was still largely just diodes, resistors, transistors and relays. The world of machines was still controlled largely by relays.
And the authors comments about relays are completely off base. By that time control relays had long been dust proof, sealed, and very reliable. And now they are also low cost.
The relays he describes are from the 30's.
Never read the book, never heard of the book.
Wow, never heard of that ones. The classics were always Linn Westcott's and the two volumes of the Paul Mallory ones. Mallory's went into such things as proper cable lacing technique - so neat and elegant compared to wire ties, but wire ties are faster so lacing just isn't done like that any more.
One of my coworkers found this book in an antique store and bought it for me.
The book is nearly impossible to read, unless you are a complete nerd-junkie like I am.
I have never encounred another such academic study of "electronics" in model railroads. The book is from 1977, and 90% of the "electronics" are just fancy DC wiring.
Does anyone else know anything about this book?