Help to id a block light

Well, the look screams out Marx, but I don't have a diagram for it.

This may be of some help:

http://www.thortrains.net/maracc6.html

Marty

GRJ Yup I thought Marx also

Martin I had found that link but it does not address the coil and rheostat connections

Larry

Wow

I can not believe I have stumped all the excellent talent on the OGR forum

I have tried different hook ups and think I know where most of the wires go.

I still do not know the purpose of the rheostat or where the wire going to it's lever hooks up.

Larry

I have a hunch that is a poor mans stopping signal.  It seems that the center rail is insulated at each end of the stopping block.  When signal is red, the train stops, when green, the center rail has power, the rheostat may be some sort of timing device or a way to manually stop and start the trains, sort of like the old pre-war standard gauge trains that used the 92N (?) block signal, I think this was Marx answer for O gauge...

Marty

Can you post a pix of the side with the lever on it?

Here are two more pics one of the outside and one inside

Larry

Thanks for the photos. All I know that is is rare. I have seen hundreds of Marx block signals, and yours is the only one I have seen with a automatic train control. Must have been a very short run. I have never seen any directions for it either. Probably works very similar to the Lionel 253 automatic block signal. Not sure of the purpose of the relay coil, however.

Wonder if rehostat is actually a heater for bimetal strip that turns the center rail on off. Or that rehostat adjusts the current to bimetal heater to lengthen/shorten interval time period.

IDM,

Anyway to diagram how wires are connected to various parts?  If we see that, pehaps we can figure out what it doing and hookup.

Sure is a lot of parts for a Marx signal, it is unusual.

I agree with Sam, try to draw a diagram of exactly what you have in the signal, then we may be able to figure out what it does.

Ok

Lets see if you can make out my hen scratching

I do know that the coil will switch the lamps from green to red but am lost on where the two loose wires go and the function of the rheostat

Larry

Given the heavy wire on the coil and from relay to base, and what appears as a copper washer on the relay pole, I suspect that when the train enters the insulated track, the engine current passes through the coil activating the relay switching the lamps.  Not sure what the copper plate is between the relay and the signal base, perhaps a bimetal timing device. 

How is the resistor rehostat positioned relative to the lever, ie lever touched rehostat winding or was it positioned well away from lever?  I suspect the lever was a (now disconnected?) switch to bypass/disable signal so train kept going. 

Here is my professional () opinion. I agree somewhat with RRMan. The method of operation I envision. A engine would enter a insulated track section, my guess is one of those long snap on copper rails Marx provided with their signals to the CENTER rail.

 The engine would stop on the insulated center rail, but what looks to be the coil resistor would limit the current so the reverse unit would not drop out. The light would be red. I am suspecting a push button was also provided with the signal. The push button would by-pass the resistor and also feed current to the magnet coil and give full track voltage to the center insulated rail and change the block light to green.

 The lever on the side of the signal is just a on/off switch which would by-pass the resistor coil and the light would always stay green so the train would not have to stop every time it made a pass and the operator would have to press the 'start' button.

from a pdf document on this automatic block signal in the marxtrain Yahoo group, here is a diagram of the signal with the intended use as a two-train control.

the 4 page writeup has much more information on its operation and limitations.

cheers...gary

I would like to thank every one for their input

It looks like the schematic that overlandflyer posted is what I have

could i ask if you can verify the position of the lights as accurate to the drawing?

just wondering if Marx inadvertently put the red light above the green.

thanks...gary

Gary

The red light is on the top

Larry

with the high ball (green) signal for railroads predating automobiles by quite a few years (and busy intersections by even more), i wonder how the red-over-green traffic light came into existence.

I am going to take a wild guess on this:

On the RR, engineers get a prewarning one block ahead that a red signal might be ahead, so they can adjust their running accordingly.  However a motorist does not have a prewarning as such (yess there is yellow/amber, but its on same pole), so the red is on top to give the highest and possibly furthest warning ahead to a motorist, especialy if coming over top of a hill.

Then too a RR signal should not have snow accumulate in red, so its positioned on bottom so snow drops out.  Snow will accumulate in traffic signals but I assume motorist would be more cautious (yea, right!) if red not observable.

Just best guess here.