Prototypical light operation question...


Eta power

Eta power

EMD 645 V-20 Turbo
First, hello, I'm brand new here and I hope to get the most I can out of this forum.

Second...
I have two Athearn SD45T-2's (#'s 9316 & 9325) that I hope to retrofit with LED's, but I have a question about the lights operate...

I think that when the lights are on "low" light 1 would be dim and light 2 would be off. Also, I think when the light are on "high" that they would look as pictured. If I remember correctly the red Mars light (#3) was only used in emergencies/for warnings. Any help is appreciated...
lightsa.png
 
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Lights #1 is the Mars warning light. Light #2 is the headlight. Light #1 would not be dimmed, just on or off, also a real Mars light would be able to be stopped and aimed. Light #2 would be the one that would be dimmed and Light #1 would be off.
 
*Original post edited slightly for clarity*


I was under the impression that #3 was the Mars light and #1 & #2 were headlights. :confused:
 
Light #1 is the mars warning light. Light #2 is the headlight. Light #3 is the signal light. Light #1 is used for going down the track to make the train more visible to motorists at grade crossing, as the moves the beam of light around in the figure 8 motion. Light #2 is the normal headlight that projects the light beam straight down the tracks. Light #3 is the signal light, most effective when operating on double track, it turns on when the trains brakes go into emergency, to warn trains on the other track that there may be a derailment along that train, and could be blocking the other track. Its light pattern is in a circle.
 
SP4439,
Thank you for the calcification.

diburning,
Thanks for extra info; now I know how to program that light when I retrofit a NEC decoder on theses locos.


-Eta power
 
Everyone calls it a gyralight. If you want to get technical, then you're correct but if you buy a decoder and it has a list of lighting functions, most of the time it will say gyralight.

It's a brand name that became generalized as a common noun, like Kleenex, Saran Wrap, Xerox, Post-it, Wite-Out, CrockPot, Jacuzzi, Band-Aid, Zip-Loc, ChapStick, Vaseline, and Aspirin
 
It appears that different headlights are being confused. To make it perfectly clear, what the SD45T-2 model is equipped with are Pyle-National brand Gyralites. They were the preferred signal light supplier for SP and SSW throughout the 1960s until they discontinued signal light usage in the 1980s. Their lights swept the light beam in an oval pattern.

The other signal light brand used by SP, on steam engines and early diesels, were made by the Mars Co., which happened to be related to the candy manufacturer. Their signal lights generally swept the light beam in a Figure-8 pattern.

Aside from the differences in light pattern, the casings were different as well, which can usually be noted on scale models. On Pyle-National Gyralite dual signal lights, the front of the hinged casing has a pair of hinges on one side, and a single tie-down screw on the other. Mars-brand lights had a pair of hinges on one side, and a pair of tie-down screws on the other, plus large gaskets surrounding each lens. And the single beam lights commonly used on the noses of SP diesels were different between the two brands. The Pyle-National light had a rounded case, whereas the Mars equivalent had a squared case.

More info on Pyle-National Gyralites here: http://trainweb.org/gyra/gyra.htm

And Mars signal lights here: http://trainweb.org/gyra/mars.htm

And as others have mentioned, for lighting effects on models, there are differences, so program your models accordingly.
 
The #17540 single Gyralites with the red PAR 46 bulb were the standard SP signal light, seen as number 3 in your model. Athearn did a good job representing the hinges, by they left off the four raised, decorative ridges on each side of the light, at least on the SW-1500 I've seen. It's a small detail, but irksome to someone who watched SP trains for about 35 years. When the SP was removing the light cluster from the rear end of most locomotives in the late 70's, I had a shopman at Taylor Yard give me a one, since it was going to be trashed. I built a 32 volt power supply, and it was a neat addition to the train room. That thing sure was bright. Looking at it for more than about five seconds destroyed your sense of balance for a while. :)
 
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