I will need about HO scale 24 PRR amber signal disk and oval heads + 24 color signal disk and oval heads. 24 of these PRR signal heads will be color LED’s to simulate Amtrak’s North East Corridor. Another 24 PRR signal heads will be amber. All together I do know that I will need 12 amber PRR disks + 12 oval heads = 24 amber signals. 12 color PRR disks + 12 oval heads = 24 color signals. 24 amber disk and oval signal heads + 24 color disk and oval heads = 48. 7 lights in one PRR disk or oval = 7X48 = 336 LED’s!!! What size LED’s will I need to fit inside the holes of the signal heads. I am looking for pre wired 12v LED’s. I don’t know exactly how the colors are arranged on the signal heads. I do know that there are 7 lights on each signal heads, but for each signal head how many reds yellows and greens do I need for one PRR signal head which has 7 lights. Will I really need 336 LED’s or is there another way around. I really need help with this. I need all the help that I can get. I will be using these with my Digitrax SE8C.
You might want to ask this in the Prototype information for the modeler forum.
Tom
Check out this youtube video taken on Amtrak’s Keystone Corridor.
http://www.youtube.com/watch?v=s0vB6H7xhqM
Several scenes of color position light signals showing a nice signal progression as a train passes and proceeds down the line. Please note that these are still PRR style aspects and are not to be confused with B&O style CPLs.
Or he might want to occasionally exercise the internet: http://broadway.pennsyrr.com/Rail/Signal/aspects_us_pl.html
PRR used only amber lights on its signal heads. The position of the light conveyed the signal aspect.
B&O did similar, but omitted the center light and used colored lamps in addition to the position to convey the aspect.
AMTK today does it similar to this, but the LION is not sure exactly how, him having moved to North Dakota almost 30 years ago.
The LION builds his own signals from scratch. Use plastic discs, perhaps punched out of pop bottle tops (Get the correct size gasket punch in a plumber’s store), drill holes for your LED, and wire them from the rear. Use a little chunk of modeling clay to occlude any back scatter of light and paint the wires black.
The size of the holes depends on what LEDs you will use. The smaller LEDs (T-1) are 1/8th of an inch in diameter, and so a 1/8th inch bit will do it. (Lamps are measured in 1/8ths of an inch… the letter T indicates the shape (Tubular). Old florescent lamps were T-10s, newer ones are T-8s, Table lamps were P- something (Pear shape) or PAR for parabolic reflector). The larger LEDs are T-1½, I think I use either a 5/64 or a 7/64 bit for those, but test that out on scrap material first because LIONS are not too good at remembering things in general or numbers in particular.
DONE!
ROAR
Replies from duplicate threads on three forums have been merged here.
Posiiton lights with colored bulbs are on former B&O trackage - that is the type of signal the B&O used, similar to the Pennsy but with colored bulbs and no center light. The all amber lights witht he center bulb are PRR signals and basically imitate a semaphore by the position of the lights, vertical, angled, or horizontal.
–Randy
Randy:
He also asked about Amtrak, former PRR, signals. I think they use two red lights in the horizontal position. I believe I read that this is to indicate absolute stop.
That would likely be an absolute stop, not sure where the PRR would have used color signals though. I was just lookign at some signal diagrams for the Reading including some spots were the Reading and PRR crossed and the signals ont he PRR side of the interlocking were always position lights, not colored lights.
–Randy
From what I have read on the Pennsy/former Pennsy signals, two horizontal red on the top target was used at interlockings where a train would not be allowed to pass a stop signal without permission. Other signals used the three horizontal amber lights for a stop signal.
Kevin
It’s all red, or it’s not red at all.
ROAR
Will I really need 336 LED’s or is there another way around. I will be using these with my Digitrax SE8C.
You need 336 LEDs. Or buy pre-made, such as NJ International (not cheap). There’s really no way to fake it. All the PRR signals might not need 9 LEDs though - for sidings a dwarf was often used which has 4 lights instead, and the ‘pivot point’ one would always be lit regardless of the aspect (same with the middle one on a full signal). You might also be able to cheap slightly for the dwarf signals on sidings since there might only be 2 possible aspects, stop and restricting. That cuts one 1 LED on the dwarf. FOr multiple head signals on interlockings, if one head could only possibly display one or two aspects, teh lights required for the unused aspects were left out since it would be one more thing that required maintaining even though it wasn;t ever used. So on some of your signal masts you may be able to reduce the total LED count somewhat by eliminating LEDs for aspects that can never be displayed anyway.
See here: http://www.ctcparts.com/about.htm
and here: http://cg-tower.com/cpl/
and here: http://rrsignal.com/railroad/signals.htm
–Randy
Thanks for your input. I’m a little intimidated on how much 336 LED’s would cost. There’s a section of my layout that has 13 through tracks which can be also used as a part time yard. I have already bought 2 4 track signal bridges with 4 disc signals on the top and 4 oval signals below on both sides for bi directional travel which is 16 signal heads per one 4 track signal bridge. I will purchase one more 4 track signal and one signal mast bridge to complete the 13 track layout. I will be using these with my Digitrax SE8C.
A pack of 100 LED’s cost about $2.00 here:
http://www.mpja.com/LEDs/products/116/
The 3mm size will work for the Oregon Rail Supply heads if you open up the holes a little bit.
But you are also going to have to buy resistors for each of them. 1K ohm at 1/2 watt for each pair should work. Just get a few to test them to see if they are bright enough for you. Just don’t go lower than about 470 ohms. if using 12 volts to light them.
EDIT
If you are using an SE8C and the signal mast base kits, then you won’t need extra resistors, as the signal mast base kits have them already installed on the base kit circuit board.
Remember to follow the instructions for PRR position light signals, it used to be a seperate download on the Digitrax site. It does make a difference because on an ordinary 3 light signal you have just 1 LED to each pad on the signal base kit, and the included resistors are just right. PRR position light signals and B&O color position signals have multiple LEDs per output.
Here: http://www.digitrax.com/se8cposition.php
WHat you need are some extra diodes, not resistors. Radio SHack has them in 50 packs for 3 bucks, but you can get them just about anywhere for far less, Like here on Amazon for 1 cent each: http://www.amazon.com/Parts-Express-1N4148-Logic-Diode/dp/B0002KRC7C/ref=pd_cp_e_1 or here from Newark Electronics: http://www.newark.com/jsp/search/productdetail.jsp?SKU=58K9617&CMP=AFC-GB100000001 qty 300 would be 1.2 cents each so a whoppign $3.60 for 300. You probably don’t need 300 though, each PRR signal head needs 6 of these diodes, 5 for absolute signals. so you need more like 140 or so, little over $2 worth.
–Randy
I thank you for your effort, input and the information you’ve provided. What is the difference between resistors and diodes? How do I know which resistors and diodes I need if there are many types out there?
I thank you for your effort, input and the information you’ve provided. What is the difference between resistors and diodes? How do I know which resistors and diodes I need if there are many types out there?
I’ve been building PRR signals at the club layout for several months now. We have Nine 4 track signal bridges done and working so far.
7 of the bridges are from Oregon Rail. 2 of the bridges are scratch built.
For LED’s I went on ebay and purchased 1.8 mm Dome type. They were $10.50 for packs of 100.
To install them I first coat the inside of the target with CA accelerator and let it dry.
Then I put a coat of medium CA on the led’s and press them in. With the dried accelerator they adhere within 5 seconds.
Then I wire them up.
The whole process takes about 9-12 man hours per bridge. It gets boring and tedius but it’s worth it. Here’s a few pics.
Here’s a few closer up pics
