I'm getting to the point where I'd like to automate the signals on my Santa Fe HO scale layout.
The layout is very simple. Two main tracks with a spur and a crossover. There are also some sidings. Trains normally travel in one direction.
Below is a diagram of the signals on my layout (click it to make it bigger)
*note the Seachlight signals are Tomar so they will need yellow aspect hue control
I use a Digitrax Zephyr for DCC control (may change to Zephyr Xtra). There are presently no cuts/blocks/sections on the layout.
A must for the signaling control is Flashing Yellow
I've done lots of research online into various signal control manufacturers. But very few seem to offer flashing yellow as an aspect.
I also do not want to use a computer to control signals.
What signal system would you suggest for my small layout with only 4 blocks on one track and 5 on the other and a few turnout signals?
Should I use current sensing or optical sensing for the blocks? I do lots of night operations so IR would be the only optical possibility. I also run the same trainsets most of the time, so adding resistance wheels to the last car of my trains would be super easy.
Matt from Anaheim, CA and Bayfield, COClick Here for my model train photo website
I would take a look ar RR-CirKits and their TowerMan and SignalMan products, along with coil-type current based detection. The key is how their controllers work via apsect rather than defining a signal head with 3 colors and making the control side (something like JMRI or RR&Co) generate the aspects. Why is this important? When done at the PC/logic level, a flashing yellow ends up being an endless series of Loconet commands - yellow on, yellow off, yellow on, yellow off. Too many of these and you just flood the Loconet with these messeges, causing problems with train control. The aspect-based methos used by the SignalMan board, the software says to display a specific aspect. If that aspect includes a flashing yellow, or a flashing anything else, the flash is generated by the local board. The software sends one command - "display medium clear on signal 212W", the SignalMan board handles turning on the correct LEDs in the signal.
Our club modular layout is fully signalled per modern NORAC practices using JMRI. As such there are lots of flashing indicatioons. Digitrax SE8C boards were used - they are basically 'dumb' boards that turn outputs on or off based on switch commands. To get flashing yellow, there was the constant "on,off,on,off" command sequence and with lots of signals, it caused enough problems that the layout now has 2 independent Loconets, one for the signals and detection and the other for the command station, boosters, throttle plugs, and radio receivers for train operation.
For block occupancy, without neededing to fuss with available light, the resistence wheelset method is probably the best. Using current transformers like the RR-CirKits instead of the didoe drop used by the BDL-168 means there is no voltage drop to the track, and if you have sections where there is no detection, there won't be a voltage difference between those sections and detected sections.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Current detection would be the way to go. It is not light dependent and will work with DC as well as DCC. NCE BD-20's are easy to figure into a circuit and they'll work crossing flashers as well as signals. miniature relays are controlled by the BD-20's to give you red, yellow and green aspects. I don't know about flashing yellows or greens but you could hook in a flashing module to make them flash. Dallee electronics makes a flasher module that I use for crossing flashers. You could make a flasher buss and use it for any flashing leds you may want. One flasher module for all the aspects you want to have flashing would be enough.
The circuits for my signals were posted somewhere on this site many months ago on two pages, one for modules and the other for a home layout. I have them on a couple of N scale T-Track modules and they work well and look good. They are strictly automatics but they are easy to modify for displaying routes if you have switch machines with auxiliary contacts.
Thanks for the replies. Great info and some leads to look into.
There are two kinds of signals.
Interlocking or Home Signals are controlled by hand from a lever in the tower, they show the position of switches and/or the speed allowed through a plant.
Block Signals are automatic, out on the railroad, and are controlled by detectors embedded in the tracks. You have limited youself to current detection or optical detection, but you have not yet detetected all of your options. The LION embeds reeds switches in the gauge of the track, and placed magnets under his locomotives. Hey it 1) works; 2) is cheap; and 3) the electronics is easily understoot by a LION who can have no truck with mystery stuff incased in a myatery chip.
The LION uses relays to control the block signals of him. Here is realys room of LION:
Looks complicated, it does, but not it is.
The diagrams are printed on the paper, but of course only remind me of what I am trying to do.
1) When a train rolls over a detector, it PULLS the relay (say the Avenue H relay). That puts a red indication on the tracks between Smith-9th Street and Avenue H. It also puts an indication on the MODEL BOARD that Avenue H is occupied. It also turns off the starting relay at Smith 9th Street so that a train cannot enter the RED block.
2) When the timer clears the train to leave Avenue H, it will cross the detector before Cortelyou Road. This will momentarily energise the holding relay at Avenue H, releasing the the Avenue H relay. This sets the signals between Avenue H and Cortelyou Road at RED, it also lowers the indication between Smith 9th Street and Avenue H to YELLOW, and movest the indication on the model board from Avenue H to Cortelyou Road. Following trains can depart Smith-9th Street, but will be held at Avenue H.
3) Whe the train departs Cortelyou Road it activates the detector ahead of Parkside Avenue. The Line from Cortelyou to Parkside displays RED, the line from Avenue H to Cortelyou displays yellow, and the line form Smith-9th to Avenue H displays Green. Following trains cannot depart Cortelyou Road. The model board keeps track of the train locations.
Here is model board of LION. It only displays locations of trains, there are no controls on the model board. Switch points are controled by the GRS Interlocking Machine.
There are five conductors between the Relay Room and the Layout. These Are:
1) The Detector tracking the location of the train
2) RED indication for the block behind the train
3) YELLOW indication for the second block behind the train
4) GREEN indication for subsequent blocks behind the Yellow Signal
5) The TIMER circuit to release trains from a station. If you are not using stations as your blocks, it will nonetheless cut power to the red block so that a following train there would be brought to a stop.
The LION stands in the middle of things and watches the trains go round and round. That *is* what LIONS do.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
OK, it is true that on layout of LION him uses three lamp targetless signals after the New York City Transit Authority. After all, layout of LION is a subway layout.
Him uses three LEDs, a common ground via a 1K ohm resistor, and three conductors to the control (realy room).
All well and good if LION you are, and are building a subway system, yes?
But ewe on the udder hand have different ideas. You want a searchlight signal. Searchlight signals is nothing more than a little itty bitty semiphore signals hiding inside of a case filtering the light through a bank of lenses. If circuit fails, signal falls to RED.
Ewe Want to build one of these, I assume you do not want to make little itty bitty clockwork mechanisms to filter light. LION gueses that you will use a bi-color LED, as that is what him would do if him were to build the zoo with that kind of a signal. ONE lead of LED goes to GROUND via a 1K ohm resistor. All well and good.
Now you have the other lead in your nice soft furry paw. What to do with it. LION would get a simple 12v AC wall wart. Him would cut off the plug and affix one wire to ground, him cares not which wire, it makes no difference at all.
Next you get two rectifires, so that you will have THREE outputs: 1) +12v dc; 2) -12v dc; and 3) 12v AC. Since you want a flashing amber indication, you will have to make a fourth outputL Interupted AC. LION know knot a circuit for that, maybe you will have to hire a SNAKE to sit there and push a button to flash the signal. Hey it works for me, and when you are done playing with the trains you can cook the snake in a soup.
You say something about Tomar signals? LIONS know nothing of Tomar signals: Signals of LION cost him 12c each. If your signals cost more than 12c then your layout is clearly not big enough. With over 200 signals on layout of LION, purchased signals are out of the question. The zookeeper will simply not hear of it. Nope. it is just not possible.
ROARING
HEY RUBE! Your LION is on the loose again!
Interesting, and comical reading as always Lion. Thanks for the info.
Didn't think the old relay style of model railroad signaling control was still used much. But awesome to see it's alive and well in Lion's jungle
Actually relay controlled signals are still in use on the NYC Subway and there are still many lever controlled interlockings too. My drawings are based on their automatic signal controls still in use. Modern pushbutton interlockings and computor control are becoming the norm though.
retsignalmtrModern pushbutton interlockings and computor control are becoming the norm though.
Doesnt matter how many computers you have, the relays are still there. Perhaps they are no longer used for the interlocking logic, but you need the relays to translate little itty bitty computer power to the bigh hefty railroad power that it takes to move points and light signals. Those call for RELAYS.
For Block Signals, you will always need relays to detect the presence of a train, and to provide the signal logic as the train moves down the line. Even if you use optic fiber to move the signals, you still need the relays to provide the logic and to light the lamps.
GO RELAYS!
Maybe for operating powered turnouts, but the detection stuff is all electronic now. It was over 15 years ago I got a guided tour of the workings of a grade crossing, and this was on a barely used line. That big cabinet that used to be full of relays to detect the train and operate the gates and flasher was all but empty. There were two or three circuit cards, one of which was the battery charger, and a small sealed lead-acid battery for backup power. The battery caller in the ground that used to hold a bunch of Edison cell batteries was just full of spiders. This electronic system could detect the speed of an approaching train and adjust the timing of the gates as needed, so they didn't come down too soon and block traffic for a slow moving train that was nowhere near the crossing yet, while getting them down soon enough for a faster moving train so there was plenty of time for cars to stop. Faster being relative here - at the time, the line had a 25mph limit.
rrinker Maybe for operating powered turnouts, but the detection stuff is all electronic now. It was over 15 years ago I got a guided tour of the workings of a grade crossing, and this was on a barely used line. That big cabinet that used to be full of relays to detect the train and operate the gates and flasher was all but empty. There were two or three circuit cards, one of which was the battery charger, and a small sealed lead-acid battery for backup power. The battery caller in the ground that used to hold a bunch of Edison cell batteries was just full of spiders. This electronic system could detect the speed of an approaching train and adjust the timing of the gates as needed, so they didn't come down too soon and block traffic for a slow moving train that was nowhere near the crossing yet, while getting them down soon enough for a faster moving train so there was plenty of time for cars to stop. Faster being relative here - at the time, the line had a 25mph limit. --Randy
Axle counters that count the number of axles entering a block and calculate the trains speed are coming into use on the NYC subway after the crash at Union Square. They calculate the speed on diverging routes that have speed restrictions. They can also be used to eliminate the insulated joints, transformers and track relays of the track circuit.
Pretty sure there were no other batteries. When I say small, I mean it wasn't as big as a car battery. Somewhat larger than the SLA in one of those stair lifts that can move 400 pounds up and down a stairway multiple times on a single charge. I don't think it takes much power to move the gates, unless someone tore off the counterweights. This was an I stallation with just one gate on each side of the tracks - I witnessed a passenger bus drive around the lowered gates without hitting anything. the owner of this bus company was the one person who managed to block all attempts to establish a passenger service over an unused line that would have been a huge boon for commuting workers. His work is now done, most of the rails have been torn up and highway traffic just keeps getting worse.
Randy you might have just missed seeing them but the lights alone draw about 10 amps I dont remember how much the motors draw they are 12 volt the ni-cads we used for crossing protiction were about 18 inches tall we used smaller ones for track circuits also if all power is removed from the crossing the gates will drop down there is a hold up relay in the mechanisam its a failsafe one of many at crossings also if someone was dumb enough to remove the weights I think the motor could lift it up but when it released to go down it would drop like a rock Not sure what the one batt was for unless for the island circuit
Maybe, but I'm pretty sure the maintainer showed use the entire system. Definitely an SLA, recognized the designation from the ones that appear in computer ups systems.