Does the MARS light always go on top on an E7?

[mmagliaro]

So, I'm still rebuilding this Broadway Limited special-run SP&S E& (#750).
It has dual headlight lenses, top and bottom.  Does the MARS light go on top? 

[nickelplate759]

This photo suggest that SP&S 750 had the Mars light on top. The hint is that the lower light (headlight) is on, but the Mars light is off.   The other way 'round would be unusual - although both on is also common.


I've never seen a cab unit with the Mars light on the bottom, but I imagine it could have been done.

George

[mmagliaro]

Thanks!

So... how common was it that an engine would run with the MARS turned off?  I somehow always assumed that if an engine were equipped withone, it would be on all the time.

[arbomambo]

Mars light was activated at crossings, foul weather,  emergencies, etc...
Bruce

[Ed Kapuscinski]

Also, keep in mind, there's a whole "thing" about those lights.

There are the red ones, and the white ones. And a whole bunch of differences in there. Take a look:
http://www.trainweb.org/gyra/mars.htm

[mmagliaro]

Also, keep in mind, there's a whole "thing" about those lights.

There are the red ones, and the white ones. And a whole bunch of differences in there. Take a look:
http://www.trainweb.org/gyra/mars.htm

Thanks, Ed.  Yes, I have been doing a lot of reading on them...  I will probably just model the kind
that ramp up, flash, then ramp down, ramp up to a lesser flash, and so on, in a repeating pattern.
The figure 8 mechanical gyrating ones are cool.  I was briefly pondering the possibility of making an actual, motorized, working MARS light
that would physically move a tiny SMD LED around... but I have since come to my senses.

I don't know what type was inside the SP&S engine.  Can't find video of the front of that thing running.

[peteski]

I was briefly pondering the possibility of making an actual, motorized, working MARS light
that would physically move a tiny SMD LED around... but I have since come to my senses.

Even if it was feasible to create N scale size mechanism to move a tiny LED, the effect would not be optimal. The small SMD LEDs have very wide viewing angle. Mars light has a incandescent bulb with a reflector which tightly focused the light into a tight beam. That resulted in the distinct flashing pattern. It is not really feasible to make such reflector in N scale.  Even just painting over the LED housing and then scratching a pinhole size aperture would still not result in a focused beam.  Maybe using a laser LED woudl work... but those are rather large. 

[nkalanaga]

mmagliaro:  Either MR or RMC had an article MANY years ago on doing that, but I can't remember when, or even if it was HO or O.  If you can find that article the mechanism may be scalable, but I wouldn't guarantee it.

[Missaberoad]

mmagliaro:  Either MR or RMC had an article MANY years ago on doing that, but I can't remember when, or even if it was HO or O.  If you can find that article the mechanism may be scalable, but I wouldn't guarantee it.

I seem to recall it was in HO and pretty much took up the entire interior of a dummy cab unit...

[mmagliaro]

Well, I've decided to try to cook up something of my own.  I'll keep you posted.
NGineering makes a tiny little module that is designed to power 3 SMD LEDs, which you must
deftly solder together into a tiny little package and shove up in the light housing.
The module then glows the various LEDs, dimming and brightening them in a pattern.

I've seen it in operation at a train show, and it is impressive.  Best simulation of that moving MARS light
I've ever seen.  But like I said, I'm going a little more conservatively - just a pulsating one will do.